You can ask anything you wish and it's a very good question.
I am not there to rag someone's road car to 100% of its ability. On the limit anything can happen and I am not going to take any risks when I have a passenger on board, with or without insurance, it's just not my style.
When we get to race cars, it's slightly different. As with most track day drivers, many rarely get within 70% of the cars actual capability, as they them selves don't have the experience or ability to go beyond that straight away. With race driver tuition in race cars, we have telemetry to compare to, so I can go out and push the car, without a passenger and then compare the clients laps to mine, sit down and talk through it ect ect.
I am there to teach you how to get the most out of your self and your own ability; not show you how well I can drive your car on its limit.
Correct me if I am wrong please, but where does it say that I will personally drive your car at 100%?
My main point being is that most people will not take anything in when I am driving very fast either, as they will be hanging on for dear life. In my experience, the slower laps, talking my way round and demonstrating the techniques are far more beneficial then going flat out with the client for 3 laps.
Hope that answers your question? If not, say so.
Ps, maybe I am wrong, but I personally respect other people's property and safety, if someone asks me to really go 100%, then I might consider it once I have all the insurance in place, but no Guarantee’s.