I like Troy's approach as well. Partially for the walk down memory lane, and partially because he is spot on with getting you passed the bad habits many of us have built over the years. He has certainly put a lot of time and effort into this program and he does a good job at explaining in detail the minute adjustments that really make a difference in increasing your speed.
This is been explained many many times, but never to this extent and not exactly this way. Troy is definitely onto something with his pick slanting approach. All of these guys do it, they just don't know that they're doing it, so they don't explain it. Troy use slow-motion video capture to analyze the techniques and you can definitely see it in the videos. It's more than just economy of motion, it's also eliminating sticking points that bog you down when changing direction. It's funny when you think of how Yngwie explained this in his early instruction videos "I move the pick up, and then back down again" "I use a Fender medium pick" shows it to the camera... haha!!!
I realized when going through the program that I am actually using pick slanting on some of the patterns that I'm able to play quickly. Patterns that felt comfortable to me, where I had adopted this technique naturally over the years. Again, I had no idea I was doing this. In other things which feel awkward and clunky, where I get jammed up like I fell off the tracks, I'm incorporating these techniques, but as we know, it's difficult to relearn after years and years...
If you haven't already seen Troy's stuff, you might want to take a look on YouTube. Where was this guy when I was 15 ?! I could have learned it right the first time!