diff --git a/app/scodoc/sco_formsemestre_status.py b/app/scodoc/sco_formsemestre_status.py
index 61053f74..286bcf11 100755
--- a/app/scodoc/sco_formsemestre_status.py
+++ b/app/scodoc/sco_formsemestre_status.py
@@ -73,7 +73,6 @@ from app.scodoc import sco_formsemestre
 from app.scodoc import sco_formsemestre_inscriptions
 from app.scodoc import sco_groups
 from app.scodoc import sco_moduleimpl
-from app.scodoc import sco_permissions_check
 from app.scodoc import sco_preferences
 from app.scodoc import sco_users
 from app.scodoc.gen_tables import GenTable
@@ -340,6 +339,7 @@ def formsemestre_status_menubar(formsemestre: FormSemestre) -> str:
         },
     ]
 
+    can_change_groups = formsemestre.can_change_groups()
     menu_groupes = [
         {
             "title": "Listes, photos, feuilles...",
@@ -352,27 +352,20 @@ def formsemestre_status_menubar(formsemestre: FormSemestre) -> str:
             "title": "Modifier groupes et partitions",
             "endpoint": "scolar.partition_editor",
             "args": {"formsemestre_id": formsemestre_id},
-            "enabled": sco_groups.sco_permissions_check.can_change_groups(
-                formsemestre_id
-            ),
+            "enabled": can_change_groups,
             "helpmsg": "Editeur de partitions",
         },
         {
             "title": "Ancienne page édition partitions",
             "endpoint": "scolar.edit_partition_form",
             "args": {"formsemestre_id": formsemestre_id},
-            "enabled": sco_groups.sco_permissions_check.can_change_groups(
-                formsemestre_id
-            ),
+            "enabled": can_change_groups,
         },
     ]
     # 1 item / partition:
     partitions = sco_groups.get_partitions_list(formsemestre_id, with_default=False)
     submenu = []
-    enabled = (
-        sco_groups.sco_permissions_check.can_change_groups(formsemestre_id)
-        and partitions
-    )
+    enabled = can_change_groups and partitions
     for partition in partitions:
         submenu.append(
             {
@@ -921,7 +914,7 @@ def _make_listes_sem(formsemestre: FormSemestre, with_absences=True):
             H.append("</table>")
         if partition_is_empty:
             H.append('<p class="help indent">Aucun groupe peuplé dans cette partition')
-            if sco_groups.sco_permissions_check.can_change_groups(formsemestre.id):
+            if formsemestre.can_change_groups():
                 H.append(
                     f""" (<a href="{url_for("scolar.partition_editor",
                         scodoc_dept=g.scodoc_dept, 
@@ -930,7 +923,7 @@ def _make_listes_sem(formsemestre: FormSemestre, with_absences=True):
                     }" class="stdlink">créer</a>)"""
                 )
             H.append("</p>")
-    if sco_groups.sco_permissions_check.can_change_groups(formsemestre.id):
+    if formsemestre.can_change_groups():
         H.append(
             f"""<h4><a class="stdlink"
             href="{url_for("scolar.partition_editor",
diff --git a/app/scodoc/sco_groups.py b/app/scodoc/sco_groups.py
index ecdf9b9d..e54100d8 100644
--- a/app/scodoc/sco_groups.py
+++ b/app/scodoc/sco_groups.py
@@ -26,12 +26,6 @@
 ##############################################################################
 
 """Gestion des groupes, nouvelle mouture (juin/nov 2009)
-
-TODO:
-Optimisation possible:
- revoir do_evaluation_listeetuds_groups() pour extraire aussi les groupes (de chaque etudiant)
- et éviter ainsi l'appel ulterieur à get_etud_groups() dans _make_table_notes
-
 """
 import collections
 import time
@@ -49,7 +43,7 @@ from app.comp import res_sem
 from app.comp.res_compat import NotesTableCompat
 from app.models import FormSemestre, Identite, Scolog
 from app.models import GROUPNAME_STR_LEN, SHORT_STR_LEN
-from app.models.groups import GroupDescr, Partition, group_membership
+from app.models.groups import GroupDescr, Partition
 import app.scodoc.sco_utils as scu
 import app.scodoc.notesdb as ndb
 from app.scodoc.scolog import logdb
@@ -59,7 +53,6 @@ from app.scodoc import codes_cursus
 from app.scodoc import sco_cursus
 from app.scodoc import sco_etud
 from app.scodoc.sco_etud import etud_sort_key
-from app.scodoc import sco_permissions_check
 from app.scodoc import sco_xml
 from app.scodoc.sco_exceptions import ScoException, AccessDenied, ScoValueError
 from app.scodoc.TrivialFormulator import TrivialFormulator
@@ -720,18 +713,19 @@ def setGroups(
         log(msg)
         return xml_error(msg, code=403)
 
-    if not sco_permissions_check.can_change_groups(partition.formsemestre.id):
-        raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
-    log("***setGroups: partition_id=%s" % partition_id)
-    log("groupsLists=%s" % groupsLists)
-    log("groupsToCreate=%s" % groupsToCreate)
-    log("groupsToDelete=%s" % groupsToDelete)
-
     if not partition.formsemestre.etat:
         raise AccessDenied("Modification impossible: semestre verrouillé")
+    if not partition.formsemestre.can_change_groups():
+        raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
+    log(
+        f"""***setGroups: partition={partition}
+groupsLists={groupsLists}
+groupsToCreate={groupsToCreate}
+groupsToDelete={groupsToDelete}
+"""
+    )
 
     groupsToDelete = [g for g in groupsToDelete.split(";") if g]
-
     etud_groups = formsemestre_get_etud_groupnames(
         partition.formsemestre.id, attr="group_id"
     )
@@ -811,7 +805,7 @@ def create_group(partition_id, group_name="", default=False) -> GroupDescr:
     Obsolete: utiliser Partition.create_group
     """
     partition = Partition.query.get_or_404(partition_id)
-    if not sco_permissions_check.can_change_groups(partition.formsemestre_id):
+    if not partition.formsemestre.can_change_groups():
         raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     #
     if group_name:
@@ -847,7 +841,7 @@ def delete_group(group_id, partition_id=None):
     if partition_id:
         if partition_id != group.partition_id:
             raise ValueError("inconsistent partition/group")
-    if not sco_permissions_check.can_change_groups(group.partition.formsemestre_id):
+    if not group.partition.formsemestre.can_change_groups():
         raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     log(f"delete_group: group={group} partition={group.partition}")
     formsemestre = group.partition.formsemestre
@@ -863,7 +857,8 @@ def partition_create(
     redirect=True,
 ):
     """Create a new partition"""
-    if not sco_permissions_check.can_change_groups(formsemestre_id):
+    formsemestre = FormSemestre.get_formsemestre(formsemestre_id)
+    if not formsemestre.can_change_groups():
         raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     if partition_name:
         partition_name = str(partition_name).strip()
@@ -924,9 +919,10 @@ def get_arrow_icons_tags():
 def edit_partition_form(formsemestre_id=None):
     """Form to create/suppress partitions"""
     # ad-hoc form
-    if not sco_permissions_check.can_change_groups(formsemestre_id):
-        raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     formsemestre = FormSemestre.get_formsemestre(formsemestre_id)
+    if not formsemestre.can_change_groups():
+        raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
+
     partitions = get_partitions_list(formsemestre_id)
     arrow_up, arrow_down, arrow_none = get_arrow_icons_tags()
     suppricon = scu.icontag(
@@ -1093,21 +1089,22 @@ def edit_partition_form(formsemestre_id=None):
 def partition_set_attr(partition_id, attr, value):
     """Set partition attribute: bul_show_rank or show_in_lists"""
     if attr not in {"bul_show_rank", "show_in_lists"}:
-        raise ValueError("invalid partition attribute: %s" % attr)
+        raise ValueError(f"invalid partition attribute: {attr}")
 
-    partition = get_partition(partition_id)
-    formsemestre_id = partition["formsemestre_id"]
-    if not sco_permissions_check.can_change_groups(formsemestre_id):
+    partition = Partition.query.get_or_404(partition_id)
+    if not partition.formsemestre.can_change_groups():
         raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
 
-    log("partition_set_attr(%s, %s, %s)" % (partition_id, attr, value))
+    log(f"partition_set_attr({partition_id}, {attr}, {value})")
     value = int(value)
-
-    cnx = ndb.GetDBConnexion()
-    partition[attr] = value
-    partitionEditor.edit(cnx, partition)
-    # invalid bulletin cache
-    sco_cache.invalidate_formsemestre(formsemestre_id=partition["formsemestre_id"])
+    if getattr(partition, attr, None) != value:
+        setattr(partition, attr, value)
+        db.session.add(partition)
+        db.session.commit()
+        # invalid bulletin cache
+        sco_cache.invalidate_formsemestre(
+            formsemestre_id=partition.formsemestre.id["formsemestre_id"]
+        )
     return "enregistré"
 
 
@@ -1118,9 +1115,9 @@ def partition_delete(partition_id, force=False, redirect=1, dialog_confirmed=Fal
     """
     partition = get_partition(partition_id)
     formsemestre_id = partition["formsemestre_id"]
-    if not sco_permissions_check.can_change_groups(formsemestre_id):
-        raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     formsemestre = FormSemestre.get_formsemestre(formsemestre_id)
+    if not formsemestre.can_change_groups():
+        raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
 
     if not partition["partition_name"] and not force:
         raise ValueError("cannot suppress this partition")
@@ -1163,7 +1160,8 @@ def partition_move(partition_id, after=0, redirect=1):
     """Move before/after previous one (decrement/increment numero)"""
     partition = get_partition(partition_id)
     formsemestre_id = partition["formsemestre_id"]
-    if not sco_permissions_check.can_change_groups(formsemestre_id):
+    formsemestre = FormSemestre.get_formsemestre(formsemestre_id)
+    if not formsemestre.can_change_groups():
         raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     #
     redirect = int(redirect)
@@ -1221,7 +1219,8 @@ def partition_rename(partition_id):
     """Form to rename a partition"""
     partition = get_partition(partition_id)
     formsemestre_id = partition["formsemestre_id"]
-    if not sco_permissions_check.can_change_groups(formsemestre_id):
+    formsemestre = FormSemestre.get_formsemestre(formsemestre_id)
+    if not formsemestre.can_change_groups():
         raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     H = ["<h2>Renommer une partition</h2>"]
     tf = TrivialFormulator(
@@ -1272,7 +1271,9 @@ def partition_set_name(partition_id, partition_name, redirect=1):
     if partition_name == scu.PARTITION_PARCOURS:
         raise ScoValueError(f"nom de partition {scu.PARTITION_PARCOURS} réservé.")
     formsemestre_id = partition["formsemestre_id"]
-
+    formsemestre = FormSemestre.get_formsemestre(formsemestre_id)
+    if not formsemestre.can_change_groups():
+        raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     # check unicity
     r = ndb.SimpleDictFetch(
         """SELECT p.* FROM partition p
@@ -1285,9 +1286,6 @@ def partition_set_name(partition_id, partition_name, redirect=1):
         raise ScoValueError(
             f"Partition {partition_name} déjà existante dans ce semestre !"
         )
-
-    if not sco_permissions_check.can_change_groups(formsemestre_id):
-        raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     redirect = int(redirect)
     cnx = ndb.GetDBConnexion()
     partitionEditor.edit(
@@ -1304,7 +1302,7 @@ def partition_set_name(partition_id, partition_name, redirect=1):
 
 def group_set_name(group: GroupDescr, group_name: str, redirect=True):
     """Set group name"""
-    if not sco_permissions_check.can_change_groups(group.partition.formsemestre.id):
+    if not group.partition.formsemestre.can_change_groups():
         raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     if group.group_name is None:
         raise ValueError("can't set a name to default group")
@@ -1337,7 +1335,8 @@ def group_rename(group_id):
     """Form to rename a group"""
     group = GroupDescr.query.get_or_404(group_id)
     formsemestre_id = group.partition.formsemestre_id
-    if not sco_permissions_check.can_change_groups(formsemestre_id):
+    formsemestre = FormSemestre.get_formsemestre(formsemestre_id)
+    if not formsemestre.can_change_groups():
         raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
     H = [f"<h2>Renommer un groupe de {group.partition.partition_name or '-'}</h2>"]
     tf = TrivialFormulator(
@@ -1395,7 +1394,7 @@ def groups_auto_repartition(partition_id=None):
         scodoc_dept=g.scodoc_dept,
         formsemestre_id=formsemestre_id,
     )
-    if not sco_permissions_check.can_change_groups(formsemestre_id):
+    if not formsemestre.can_change_groups():
         raise AccessDenied("Vous n'avez pas le droit d'effectuer cette opération !")
 
     descr = [
diff --git a/app/scodoc/sco_groups_edit.py b/app/scodoc/sco_groups_edit.py
index 5caba3be..4fd1e103 100644
--- a/app/scodoc/sco_groups_edit.py
+++ b/app/scodoc/sco_groups_edit.py
@@ -31,7 +31,6 @@ from flask import render_template
 
 from app.models import Partition
 from app.scodoc import html_sco_header
-from app.scodoc import sco_groups
 from app.scodoc.sco_exceptions import AccessDenied
 
 
@@ -41,10 +40,10 @@ def affect_groups(partition_id):
     """
     # réécrit pour 9.0.47 avec un template
     partition = Partition.query.get_or_404(partition_id)
-    formsemestre_id = partition.formsemestre_id
-    if not sco_groups.sco_permissions_check.can_change_groups(formsemestre_id):
+    formsemestre = partition.formsemestre
+    if not formsemestre.can_change_groups():
         raise AccessDenied("vous n'avez pas la permission de modifier les groupes")
-    partition.formsemestre.setup_parcours_groups()
+    formsemestre.setup_parcours_groups()
     return render_template(
         "scolar/affect_groups.j2",
         sco_header=html_sco_header.sco_header(
@@ -58,5 +57,5 @@ def affect_groups(partition_id):
         partitions_list=partition.formsemestre.partitions.filter(
             Partition.partition_name != None
         ),
-        formsemestre_id=formsemestre_id,
+        formsemestre_id=formsemestre.id,
     )
diff --git a/app/views/scolar.py b/app/views/scolar.py
index e63522bc..b8a4466e 100644
--- a/app/views/scolar.py
+++ b/app/views/scolar.py
@@ -923,15 +923,11 @@ def partition_editor(formsemestre_id: int, edit_partition=False):
             page_title=f"Partitions de {formsemestre.titre_annee()}",
             init_datatables=True,
         ),
-        f"""<h2>
-        </h2>
-        """,
+        """<h2></h2>""",
         render_template(
             "scolar/partition_editor.j2",
             formsemestre=formsemestre,
-            read_only=not sco_groups.sco_permissions_check.can_change_groups(
-                formsemestre_id
-            ),
+            read_only=not formsemestre.can_change_groups(),
             edit_partition=edit_partition,
         ),
         html_sco_header.sco_footer(),