Great thread. Informative! I've actually heard people say that, "on the track you need a 600, etc. etc." . But I don't see their point - for everyone. .
The reason we try to get riders to start on smaller bikes on the track is so they can learn to corner effectively and not rely on the power of the bike.
All too often, riders on big horsepower bikes get themselves in trouble on the track early on. They want to use all that power, but they haven't achieved the skill level needed.
Or, they become "that guy". Slow in the corners, and then gun it down the straights.
It's extremely frustrating to be stuck behind a guy like this, and often times leads to aggressive passes by the smaller bikes.
At our trackdays, we encourage the big bikes to take a peek behind them every once in a while as they get onto a straight. If there are bikes sitting there, let them by.
Who knows, you might actually learn something from the smaller bikes that are faster in the corners.
After all, trackdays are addicting for the corners. If your goal is just straight line speed, you can do that on any highway.