As I work to improve my right hand I find the usual problems I don't have an answer for. I play two fingers and achor the thumb variously on the pickup, e and a strings accordingly. Using the a takes pressure off the wrist, though stress on the wrist has never really been an issue. It's more about playing with as relaxed a hand as possible. However when achored on the e string is left open. I cannot play in a position that allows the thumb to be flat across both strings. Consequently the floating method is too alien to me. I find it deeply inefficient. Maybe this is an issue of the strings on my bass being particularly far apart, but I'm not sure of a solution. Usually the left hand does more of the muting for the purpose of sympathetic vibrations and such, but it isn't easy to have the unused fingers cover all 4 strings. I've watched people like Adam Niti talk about playing with the floating anchor, which is more or less how i play, and he plays on 6 strings. I can't see how it's possible to anchor with a thumb flat across the strings and still have the freedom the fingers need for plucking. I don't grab at the strings as a rule (unless i'm deliberately doing so), but some people argue that finger movement should come solely from the joint at the tip. That is as unnatural as expecting the little finger to be able to move without moving the third. In fact it seems restrictive because the whole finger moves sympathetically and to expend energy otherwise is regressive. This is part of the problem I have with the floating thumb. Also the thumb gets in the way of the fingers. Lacking an anchor also makes the act of plucking much less smooth and the subsequent tone is poor. But the big problem is the hand even if from the shoulder moving up and down; if you're playing across the strings, say on the E and G, for an extreme example, it's just an inefficient technique. Same with octaves, your hand is moving in a way that anchoring the thumb relaxes.