Come to think of it, this rule would reward Germany taking only France, and leaving Normandy and Southern France alone, in the hopes of them turning into pro-Axis neutrals, rather than trying to take the whole country out in one gulp (as is encouraged by the OOB rules).
This might give Italy a big leg up on their turn, if Germany didn’t keep some units in reserve to exploit this possibility in their non-combat phase…
On another note, a serious rules question might be raised by this house rule:
“Let’s say that the UK has some units in Normandy when Paris falls to the Germans. When I conduct my roll for Normandy, it comes up pro-Axis. What happens?”
Well, there is a precedent for a unit that begins its turn in hostile territory – ships that are built into sea zones which contain enemy ships.
In that case, during the combat movement phase, the enemy ships must either leave the sea zone, or conduct combat with the newly-built ships.
The same principle would hold with the UK units in pro-Axis Normandy: they must choose to leave or fight at the beginning of the UK player’s next combat phase.
Oppositely, if Normandy was rolled as a territory which kept its Allied orientation, of course there would be no problem as these units would behave as they normally would in the OOB game.