While I agree with you
completely that it's a horrendous way to clear a gun... we have to keep in mind that dropping the hammer on an empty chamber is pretty much explicitly what they order in most competition, after (of course!) showing clear to the RO. So what he did was a very familiar and "normal" procedure in competition...
But absolutely, the guy is (vehemently, IMO) a serious problem and he needs to GO AWAY.