I agree that current mood may have an affect on post alcohol states of mind. Though I have to say I have encountered more than just two "types". It also depends on whether someone is a habitual drinker, enviroment can play a big part too. (As in venue/place of drinking). Some people have two drinks and practically fall asleep standing up, others get very active and energetic. Then you get those who go all silent, and those who unleash a Pandora's Box of wildness (Usually shy when sober types). And I know a couple of people who seem utterly unaffected by alcohol at all.