In reply to jcoup:
Yo, you can shave off 200 meters of height gain if you leave from Argentiere instead of Cham/Praz/Tines.
Hop off the bus at the very top of Argentiere, "La Fis", and walk back down the main road past hotel La Couronne, and take the path going up into the woods behind the bakery and the hair salon. Follow all signs to La Flegere (left, left, left, right) through the Bois de la Trappe. It's still 800m of up to get to the Flegere midstation and then a load more to get up the Index, but I've found it to be much quicker than going up from lower in the valley.
Post edited at 23:29