I had a chance to ride over Khardungla Pass (~18000 feet) on icy roads. I had deflated the tyres to almost 15psi to get more grip, but there was no way she would ride straight. Even guys with knobblies were struggling.
Lessons learnt:
1. No speeds over 20.
2. No brakes\rapid downshifting.
3. No slowing down either
4. Reduce tyre pressure for more grip.
5. My guess - something like this
http://www.advrider.com/forums/showthread.php?t=418653 would have helped.
Mithun