maybe the condensed combination of the gasses in water killed them. you're right, it is irrelevant. because complaining about something so silly in a movie is just nitpicking. and it was sci fi, it was based upon the laws of science. nothing out of nature happened in the movie. there were no defiance of gravity, everything that happened was somewhat possible. besides the whole aliens attacking, which is possible in principal only.
and hate male response is the easiest thing to produce. because no matter what you can make yourself look like you get the last word. of course he only posts the hate mails he can retort against. and even if the original mailer sent a response that made maddox look like a total idiot, of course he isnt going to post it. and actually, there is a very good reason why he refers to army of darkness as the best movie ever. he probably feels its somewhat of an obscure movie. and obscure movies seem to give credibility in some peoples eyes. (he also reffered to as big trouble in little china as one of the best movies ever, another attempted obscure refference to a point). he probably feels this makes him unique. by saying movies that are generally known as bad movies as his favorite, but movies that have a cult following of some sort. just a simple way to be a provokatuer, as he obviously wants to be. anyways, the man is an idiot once again, and his over simplification of signs was for the simple minded reader with no sense of how easy it is to do what he did.