diff --git a/src/rougail/tiramisureflector.py b/src/rougail/tiramisureflector.py
index 571207616..ee493abf2 100644
--- a/src/rougail/tiramisureflector.py
+++ b/src/rougail/tiramisureflector.py
@@ -478,9 +478,13 @@ class Variable(Common):
                 keys["default"] = self.populate_calculation(self.elt.default)
             except VariableCalculationDependencyError:
                 pass
-        for attribute in ['frozen', 'hidden', "mandatory", "disabled"]:
-            if hasattr(self.elt, attribute):
-                raise DictConsistencyError(f"Sub-attributes not allowed in a '{attribute}' attribute", 100, self.elt.xmlfiles)
+        for attribute in ["frozen", "hidden", "mandatory", "disabled"]:
+            if hasattr(self.elt, attribute):  # FIXME FIXME and attribute == "optional":
+                raise DictConsistencyError(
+                    f"Sub-attributes not allowed in a '{attribute}' attribute",
+                    100,
+                    self.elt.xmlfiles,
+                )
         if self.elt.path in self.objectspace.default_multi:
             try:
                 keys["default_multi"] = self.populate_calculation(