In reply to shaun walby:
All the days from the Britannia hut are surprisingly long, as the mountains are so remote from the hut. You finish up with a long return, after you are off the mountain proper, with a short but sharp final ascent to get to the hut, just when you don't want it.
I haven't done the Grande Gendarme, so can't comment. Martin Moran gives the GG only II in ascent, a lot harder if you reverse it. He also says :
"Dry conditions are recommended, the route becomes considerably harder if crampons need to be worn"
I'll say!! A blizzard on the crux last pitch, with little or no rock gear to protect it, adds extra sporting value too.