In reply to Jack: A couple of weeks ago West Wall traverse was totally banked out, think 60 degree neve requiring front pointing rather than walking along a ledge, and looked like a very serious undertaking so we continued up a Lords Rake variation which went up and down a bit before popping out near the top.
I would imagine if the snow is soft you might be ok in spikes, but if it is hard and the steps run out half way up for any reason you could be in serious trouble in spikes.
Drop off to the left and go up Foxes tarn route, it's a nice variation and a lot safer in summer than lords rake, less stuff that can kill you!