I'm 5'8 and I really don't have very large hands. I play a jazz bass, with a jazz neck, and my hand cramps up. I went to guitar center recently upon the notion of buying a new bass and am still thinking about it. My hand, being about average to smallish for my height, has one trait that keeps it macho, a HUGE thumb. I measured it, and it's the size of my index finger. My hands are also fairly strong. My question is, will a fatter neck eleviate the problem of hand cramping, or do you need to adjust my technique somehow for my freakishly large thumb. I played a MusicMan SUB, which had a larger neck, for an hour or so and my hand felt great, so in a way I've answered my own question, but in the interest of saving money I would like to know if someone with a large thumb like me should adjust their technique somehow. Thanks. edit: remeasured thumb and it's larger than my index.