In this lesson, we will explore combining both 3 & 4 note patterns whilst alternate picking (duh). I believe it is extremely worthwhile to learn to incorporate 4 note per string ideas into your playing (picking and legato) to maximize speed. I, like many other players, began with the more traditional approach of 3 notes per string, so it has been a nice challenge relearning things in the 4 note manner. But before I explain more, let's look at the figure; a repeating idea in Eb major.
This example is to be strictly alternate picked, and repeated as many times as you like. Left hand fingering is as follows; 20th fret pinky, 18th fret ring, 16th fret middle, 15th fret index.
You might notice that despite being a 16 note repeating pattern, we're only playing on two strings; this is another key idea for picking quickly. You'll save a lot of energy (via reduced pick motion) through playing as many notes as possible on a single string. So, the less we have to switch strings, the quicker we can potentially execute a phrase; this is where the importance of 4 notes per string comes in.
As for how to alternate pick, there are many ideas, and I myself have tried a number of different methods. Currently, I play without anchoring any fingers (no pinky draggin' here!), and try to keep the pick as close to flat against the string as possible (I do not angle the pick at all). While many players angle the pick, I find there is less resistance against the string (and therefore greater speed potential) if you do not. If I'm really digging into a note, however, I will angle the pick (you must for pick harmonics, etc). But it has no place for me where speed is concerned.
I hope you have enjoyed the lesson! Let me know if you have any questions or have suggestions for future topics.