Okay, I will say officially that someone is willing to watch every lap by every driver. Therefore, if replays show that anyone intentionally abuses those areas, their points from that race will be deleted from their final tally for the night.
I have faith too. We'll use the honor system and trust that our drivers do not violate the policy on this. If they get caught either by another driver during the race or by replays after the race, they are subject to disqualification.
I like your take on this in general, but I feel like your rule of 2 tires on the rumble strip is too lenient. If common sense is the guiding factor here, shouldn't the rule be that 2 tires must remain on the track? Not only does that make more sense to me, it'd also be easier to police. If the rumble strip is the the key guideline, it opens the door for questions like, "what counts as a rumble strip?" and "what if there is no rumble strip?"