It has to do with confidence in your fellow racers.
As a first year expert you can trust the other guys to be better, hopefully safer racers and your confidence level goes up each time you're on the track.
You will go faster if you have the confidence in yourself and trust your fellow racers. It's much easier to go deeper into a corner or make a pass on someone if you have the confidence they are not a new racer, fresh out of school, and are going to take your arse out with some stupid move. ;D ;D
Not saying all new racers are stupid, not at all, but c'mon, we've all seen enough weird crap from newbies that you know what I'm talking about.