The dirt road where I store my coach is badly damaged and is uneven to the point that my coach will drag when in travel mode. Not a problem for a car with a shorter wheel base. If I raise the coach to the maximum height to slowly exit this road, can I damage the coach from the twisting caused by the uneven road when the air bags are inflated fully?
If you raise to maximum height you will find the ride to be very unsuspended. As you have already stated, it essentially makes the suspension solid, and therefore does not isolate the frame from the undulations in the road. Will this hurt the coach? Too many variables to say for sure. It won't help it that's for sure. However, we all travel what we must travel.
If I had to do this on a regular basis, here is what I would do. Raise the coach to it's max. Lower both ends manually about 2 inches. Drive the road carefully with a spotter to see if that gives you enough clearance.
Nothing scientific or engineering related about my opinion, just try to clear the obstacles without making the suspension totally solid.