I'm not entirely sure what you mean here, but I don't consider filtering
rude at all; this is why I've tried to ensure that the Roswell posts were
clearly marked so that people could filter them out.
As for requesting that people end threads, that doesn't seem like a bad
idea if it isn't of general interest; I don't plan to continue discussing
the Roswell crash both because of that and because I've said just about
everything I have to say (though I may comment some more on the
interstellar travel subthread).