This one has been hashed over an over. There are the skyGods that say they are under control at all times because they are the best of the best. Then there are the RC pilots that have proven they are the best by what they have done.
The later of the two don,t seem to have a problem with rule #9.
There are a number of factors that have been left out. The size of the aircraft, I don,t have any problem with the electric or smaller planes touching. There is another factor distance from pilot, The cool factor of the 40% down on the deck inclose is cool to watch, is it safe?????????
Can you control radio hits, gusts of wind, striping servos, engine stoping.
Myself I think rule number 9 is OK for the big planes, unfair for the smaller ones.