height limit is not about the solar panel
wind stress on the panel should be the same at any feasible height
I do know simple physics
and the higher the mounting brackets, the more leverage/stress the bracket is going to put/pull against the screws holding it to the roof
where i go i frequently brush against low tree branches, tall brackets would create the danger of catching branches and ripping the panel off the roof or at least damaging the roof
things that brush against the A/C cover and push out of the way, might snag under a panel 4 inches above the roof
