I'm pretty sure that if the French and English would have had one big push along the Maginot Line. Most of what Hitler went on were gambles and most of them payed off in the beginning. He bet on the fact that the French wouldnt cross the Maginot Line into Germany the French wanted to make the Germans attack the Line. So Hitler used that to his advantage and left defensive armies on the western front. I guess what I'm trying to get at is that if the French invaded Germany that they most likely would have been defeated. I'm pretty sure I can find some info to support my arguement