What were/are your reasons?
That varies depending on the post. I already noted that in one case it was because there was a blatantly wrong "fact" being claimed. I don't care if the rest of the post made an argument beyond that "fact", the mere stating of something that belongs only to urban myth was reason enough for me to register a "disagree".
Heck, that post where Mathias supposedly gave an argument beyond "15 seconds" was all of three sentences, and his amazing scientific "fact" was " There is probably not one day that goes by where either consciously or subconsciously you don't want to fuck the shit out of someone you saw out on the street." Which is not something that is founded in any sort of reality, like it or not. That is not a scientific statement, and it is not a statement that is backed up by any psychological testing I've ever heard of.
Many other posts I disagreed with because they made assumptions about other poster's motivations. I disagree with unfounded personal attacks. Ad homeniem attacks are not good arguments. Any post calling me a white knight was likely to be disagreed with because I hate the term, and I firmly believe it does not apply to me, and I should have the right to disagree with people who want to libel me. I strongly disagree with the idea that it's impossible for men to value the friendship of women without an interest in sex. It's not my experience, and I've known many guys who are the same way.
I disagreed with Shego's posts about a lack of sex causing strange things to happen, as I disagree with that statement, and it's not based on any scientific fact.
I disagreed with Gasbandit's "Biology says" because science does not work that way. What scientists have learned from the study of biology is a lot more complicated than the sound bite that he presented. Moreover, it's not only wrong to say that all men who refrain from having as much sex as they can only do so because they don't have the opportunity, it's blatantly false.
All in all, there was very little science presented in that thread, and I feel completely justified in disagreeing with people presenting tiny little bits of spin that don't accurately reflect the entirety of of the complex sciences involved in human sexuality.
