Lately I have been watching a lot of videos and bootlegs and what not. Anyway, I see a lot of players (Chris Chaney, Jack Bruce, Billy Gould, Geddy Lee, Roger Waters...) sometimes put their thumb on their fretting hand over the neck. Like over the E-string, I guess for muting. I read once, a while back, on here that that was bad technique. Well I do it too. But I tend to do it more when I am playing standing up with a strap then I do sitting down. Or relatively the same. Anyway, does anyone else? Thoughts, opinions?