Hi Brad, it's hard to say for sure how things would have gone if I had carried on with an unbroken shoe. I didn't get to the off-trail sections, but once I went above the 3500' markers, there wasn't much distinction between where the trail was and where it wasn't. The tracks I was making at that point were the only ones to be seen, and there was the same 2'-3' of snow on trail as there were off trail. As an indication of its depth, the plastic trail markers that are normally above eye level were at my waist. One benefit is that this likely covered much of the scrubby undergrowth.
In the end, my desire to finish the route wasn't strong enough to endure the change from a group to a solo trek. I find that starting a trip with a group spoils me a bit by establishing the expectation of having the companionship and support. If I had finished alone, it would have left both Chris and I with 20 mile hitches back to our respective cars. This was also unappealing.
So that's a long answer... to be more succinct: yes, I think the route (including off trail sections) is doable in the snow, but don't know for sure.
Oh, and thanks. I hope to get back there, too. :)