Another thing is that because Avalanche Gulch is West-facing, it typically gets soft in the afternoon so you can often either glissade or down climb without a lot of problem.* The Whitney chute is more East-facing, so it gets in to shadow sooner, meaning it often ices up in the afternoon.
*There are always exceptions. My first attempt on Avalanche Gulch was a horror of whiteout and pure ice, and I had to down climb the whole thing feeling like I was on ice skates desperately trying to find purchase, while people's unsecured water bottles rained down on us like missiles, but I, too, digress.
