I fell off mine yesterday morning, on the ice within 5 yards of the gate
It's not as if I'm not used to slippery conditions, as I used to compete in a lot of Cyclo-Cross races (not had much chance this winter, & the local season is over now)
It was certainly an interesting ride to work yesterday, & very carefully done (tend to alternate; run one day/ride the other)
Thursday was fun though, riding to the barbers in the (falling)snow, it was just a bit dodgy when I caught the edges of the speed-bumps on Lime-Pit Lane
(front wheel 'wash-outs')
Last February, I came off twice in 500 yards (same situation - rained overnight, then froze), I seriously thought I'd broken my wrist back then, as it hurt so much I 'saw stars'
Mindst you.... '20' section tyres @ 100PSI aren't that grippy on ice