According to Shimano, rear hub brake wheels should be built asymmetrically. The only answer I've ever got from anyone about this is that it somehow serves to equalize the forces when braking. Does anyone know anything about this? It seems like something that should make sense.
Also, I have also been told that wheels which are subject to torque (rear wheels, front hub brake wheels) can be built crossed on one side and radial on the other. Are hub shells really so lacking in stiffness that the non-drive/non-brake spokes don't really do anything? Even if they are subject to less force (and are not under as much tension) than the drive/brake spokes, won't they still contribute, and won't it build a more durable wheel if they are all crossed?
Furthermore, why build 1x or 2x, other than to "save weight"?