On bass - fingers & an occasional pick here or there. On guitar - NO PICKS whatsoever.
Absolutely. 2 caveats for pick use:
1) For guitar, only if you use your other fingers. You only need a finger and a thumb to hold a pick. If you're using your pinky as an anchor, you're playing guitar improperly, and need to retrain yourself. Doing so REALLY builds your forearm muscle, because that's where the control comes from, and you'll save yourself from arthritic complications in the future (by the way, this is not a debatable/discussion item. It's physics and physiology. Accept it and make yourself a better player).
2) For bass, only if the engineer in the studio tell you to use it to add a little more punch, or if you want that "picky" effect for certain rock genres (like Filter's "Hey Man, Nice Shot.").
If my hands keep getting worse, I may have to start toe-jamming.
