If you can get hurt that badly on a track without running into somebody else, that does not bode well for mucking it up on the street.
One of my former bosses told me his best friend had wanted to do a track day for years as a "safe" alternative to riding aggressively on the streets. His wife acquiesced to his request for a track day as a birthday present, and my boss said his friend was on top of the world when he got his bike on the track. 15 minutes later he was dead after high-siding. His wife saw it happen.