Matzoh, I know the bottom section of that route, and can confirm that it is NOT a good alternative to the highways if your goal is to avoid weather related road conditions. The section from Stampede Reservoir, almost to Loyalton is unpaved and very rough, and part of it is a common snowmobile route when the snowpack gets deep enough. If you make it before it snows, and have nice fat tires, it`s a nice ride, and relatively easy to navigate with good maps (don`t expect street signs because you won`t find any).
Across Sierra Valley is paved, plowed, and very nice riding, then another 15 to 20 mile stretch stretch of (smoother) dirt road just north of Beckwourth. You`ll reach pavement again at the top of the mountain, but it isn`t plowed either until almost Janesville.
The top portion of that route I`m not very familiar with, but I suspect it`s all paved and plowed year round. If you REALLY want to try it, your best bet would be to take CA routes 89 and 36 to Susanville, then pick up the top part of that RWGPS track. All in all, a nice ride for late Summer/early Fall, but pretty crazy to try in November. For what its worth, there`s a current tour on CGOAB (called "California Lima Bean") that pretty much follows your proposed route. The rider started the Henness Pass segment, then decided against it and turned around.