I find it annoying and dangerous when people ask to join your plane over and over and over. And its certainly dangerous when the pop up window appears, blockingyour view.
So:
Can the .join feature be disabled so its impossible for anyone to even try joining you.
Can you disable specific people from asking over and over by .squelching them?
BTW AH needs a more user friendly unjoin mechanism than "ALT F4", a .unjoin command would be much better.