thats why you test them on an empty bit of road before doing a trackday lol
saying that, we had a Fez ST group N rally car last year, on the road the brakes were pretty good, and at brunters during a top speed effort i was leaving the braking later and later, and being a rally car it had a lot of rear bias but i had wound on a fair bit of front...
but i still managed to lock up the rear end at 120
foooooking shat myself as the grass bit was approaching fast, and i was 90 degrees tot he direction of travel lol
god know what happened but the car straightened up and i didnt die