I agree most accidents I have seen are in the advanced group. I feel that is where their confidence, excedes their ability.
Driving in the noivce or green groups, I find that most drivers are not pushing, so mistakes can be corrected easier. Of course there is always a nucklehead, just stay away from them.
Concerning insurance. I doubt if you will find a standard insurance policy that covers track events. I am in the business and insurance cos are wise to the HPDE events.
If you are willing to walk away from a 60,000 dollar car, then the risk is yours. I would find it very hard to do. So I spend 300 for 55,000 of coverage. If you are not willing to spend that well, what can I say.
I figure a weekend event, if you have to spend the night is $1,000.00. Event cost, insurance, room, gas, food, wear and tear on the car. You have got to pay to play.
Also remember that is is also a liability issue. If a driver is negligent and hurts someone, he can still be sued, the waivers will not stop it. Your insurance will not help you. Hell now a days you do not have to be negligent to be sued.