I have not heard of Theodore Zirgas but I will have to check it out. I just watched a video on Guitar One of Frank Gambale Sweep picking. Pretty insane. On another note I tried out one of Benoits speed picking drills using the metronome like you suggested 4 picks for every beat. It worked really well and I had to work a little harder on the timing. I am still working on getting it down with scales. But this seems like it is going to get me to the next level.