I mean, come on, "Are a man who has had sex with another man since 1977, even once"
Really? I mean, I know my blood is clean. As opposed to every straight friend I have, I get my blood tested for disease, every few months. As does my magnanimous partner.
Actually, the ban is not at all, stupid as the risk of STDs especially Aids is much higher in gay community, you also have to note that the blood test are not 100%
http://std.about.com/od/herpes/f/herpesaccurate.htm the accuracy range from 92% to 99% depending on the test, and that is huge if you consider the numbers we are talking about in blood donations and risk % blood donation from gay community can be a concern