jmikami,

On the road where you use multiple gears to optimize your torque and your cadence as you shift through them to increase speed all while riding on flat-ish terrain.

On the track, you use a single gear. You only live in the optimal torque/cadence range for that single gear for a couple of seconds. You trudge under the gear for a while, then hit the sweet spot, then you rev-out and hang on ALL while fighting tough turns. That is not optimal.

That is EXACTLY like having the same driver in the same car shift through all 6 gears in its gearbox while driving on a flat road for a time trial. Then having the same driver use only 3rd gear to get up to speed then rev-out all while on a curvy road. The times will not be the same.

To look at it another way, a more simple way: Mark Cavendish can ride 75 - 80KPH on the road. If he could do that on the track, his flying 200M time would be 9.6s to 9.0s.