[quote name='ChristopherGilbert' timestamp='1341132318' post='1714028']
It is a gray area, and like most of the techniques in bass playing, I think the technique that feels most comfortable and is able to give you what you need (e.g. being able to play fast/slow etc) is the one you need to find.
My personal experience was always thumb over the top in most cases, unless playing higher notes. I've since been taught by a very competent bass teacher to fully relax the thumb and try playing the notes on the neck without applying any pressure with the thumb. I was taught a technique where you sort of pull from the shoulder and hit the notes that way, giving you more freedom to move up and down the neck. It also leaves the wrist fully relaxed and hanging while playing sitting down and standing up. I've also found, since doing it, that the neck barely moves as well which really helps as you always know where the notes are going to be.
Hope this helps.
[/quote]sorry Chris i have to respectfully disagree with your first comment.... i have a theory that most things that are good never come easy... a good left hand technique or finger/hand position is not necessarily right for the body... and going for the most comfortable position is not always the right way... falling in to that trap can lead to lazy techniques imo... sounds very strict but music accommodates music not the body..