Good points/observations made in the last couple of posts, indeed it is the French 75 FG units that are the "glue" that holds the French line together and they must be preserved in the longer scenarios if the French are to be successful, the placement of these units is vital as they must have a escape route once the German pressure is too much and the line has to pull back, so the ability of these units to move back at least one hex the same move they change into T mode is vital to their survival to move and set up on the next line wearing down the German advance as Comrade P points out.
Unfortunately I still see French players placing the FG units in hex's from which they cannot change into T mode and retreat on the same move, the continual losses this incurs just makes life so much easier for the German player who will (or should) always prioritise the destruction of these units over everything else.
It is possible that the change to the movement rules for disrupted units which post dated the release of F14
might have altered the play balance in certain scenarios, I have not seen that personally, but it is a possibility.