My take on Montignac is the following:-

Avoid sugars (especially refined ones)
It isn't really low carb... it is pick your carbs carefully (i.e. low Glycemic Load / Low GI)
It isn't even necessarily low fat... again, it is pick your fats carefully! Limit butter, especially in cooking. Poultry fats, fish fats, olive oil - they are "good"

The focus is much less on amounts of carbs / fat / protein per day and more on a balanced, heathly (i.e non supplement guzzling!) diet.

If you are confused about how to construct a menu, and I admit it is confusing until you get in to the hang of it, I'd highly recommend getting a Montingac cook book - it takes the guess work out of things, and you'll be surprised by the variety of food you can eat, even on Phase 1.

That is how I started on Montignac, and so far so good!

Happy holidays!
Spang