Look at the cassette Wiggins rode in some of the mountain stages. The ratios are huge. This proves how important cadence is for maintaining long sustained power output. If you can't spin, your legs are dead.
A while back, I scoffed when TeRuki said this guy would do well in the Giro prologue and was totally proven wrong. Now I'd say he's a lock for the silver medal, and could even shock us all and beat Wiggans. It wouldn't suprise me!