I know a decent band who played the G+T. I think it is a fine aplce to quite literally get some gigs under your belt. The DC scene is weird, with the big venues like 930, BC, or even Velvet Lounge tough to get in, you gotta be willing to play anywhere. Places like Staccato, Felix, Chief Ike's, Rhodeside Grill in arlington, are a step up, i think...but whatever, get known, get a following, get people to talk abouth you on the 930 board, who cares where you play, as long as someone is there to listen, all it takes is the ability to inspire one person...
Calling the G+T crappy just cause of the normal clientel is reserved for those of us with no musical talent. If youare a musician who wants to make it, no place is too crappy.