What does it mean when you see that a bass neck is "U" or "C" shaped? I take it means the curvature of the back of the neck, but a bass I was looking at said "a thin U neck". I'm used to pretty thin necks. Warmoth necks, like what's on my fretless, are pretty thin and have an asymetric shape, which I like. I've played basses, like my brother's Dean, that seemed to have a pretty thick neck. Comments?