Does anyone know how to tremelo pick in the classical style i.e. fingerstyle? I have been trying to build up speed for generations. I found that my fingerstyle picking got fast enough to play the solo to "smoke on the water" at full speed - which is quite fast in certain sections. However, I have heard about using a different technique to get faster.

Apparently you are supposed to group two of your fingers together and treat them as one finger. By staggering them you can get the effect of two picks for every one movement (or three picks for two movements when you combine them with your other finger). I also heard you are supposed to do some movement with your forearm to kinda rake your fingers across the string you are tremeloing on. Also, to think in terms of pulses rather than individual finger movements.

Any suggestions?