picking hand question
There's a decent amount of variation in picking hand position.
Many players anchor, because it helps them find the right string. But the downside of anchoring is it narrows the tonal variations you can get, and limits some of your technique.
Anchoring by the bridge means you're picking by the bridge - your tone will tend towards ponticello, emphasising higher harmonics - it sounds "twangier". Anchoring the pinky on the pick guard affects top vibration... not a huge deal on electric, but when you play acoustic it changes your tone (to demonstrate this, play a chord and let it ring, then place your hand on the top of the guitar - hear the difference?). How big an affect depends on the guitar's construction and materials, and on the pitches you're playing.
Anchoring either way restricts your hand to a fairly narrow range on the string. It also slows you down in switching to techniques that require your hand in a different spot, like tapping or executing behind-the-nut bends.
For many players all of that's no big deal. I can't really argue with that - if you find the benefits outweigh the disadvantages. But I let my hand float, because that lets me make more choices. It takes more effort to get used to, but for me it's worth it.
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