I think the power is only half of the problem. The pedals are much more likely to release as soon as things start twisting and bending as a result of the high forces, and the force is no longer applied directly upwards.
But you have to admit the power is massive. Quote below from Chris Hoy.
“I can’t talk about everything we do in the lab for obvious reasons but we work on stuff to improve our leg speed, high cadence work. Once a week I go in and work on an orgometer[check] set up in the lab which has a massive flywheel attached to a bike which is about 12feet long.
It has two sets of chains to make the gear even bigger. When you push down on the pedal you’d think the break was on because it just doesn’t move. They use that to measure the torque you are producing. The instantaneous torque we generate from pressing the pedal is nearly 700 newton-metres.
A Ferrari would produced 400 to 500 newton-metres (obviously they can maintain it) but for a split second we are generating a greater force through those cranks. That is what we are trying to improve, that ability to apply force quickly. You are trying to apply a force at as higher speed as possible."
And he produces way over 2000w of power on a sprint.