Okay - then how is it he can fly??? We all know that gravity is a pregnant dog, and yet he seems to display no aerodynamic ability to fly through the air??? Any explanation of how that works?

FFS, I'm not saying that I care about science in fantasy/supernatural/sci-fi settings. I'm saying that even if your story requires 'suspension of belief', you still have to maintain a sort of logic consistency within the story. If the author makes a mention of Superman having an extremely high metabolic rate that prevents him from being affected by human food/drinks/poisons/toxins etc, then the same should apply for alcohol. Though to be fair that would just be a little plothole and I don't think anyone would care about if he did drunk, unless they're pedantic.
As for superman's ability to fly, it depends on the series. Last one I read said something about him having the ability to alter gravity fields or something, a weaker form of telekinesis.