The phrases have to fall in line otherwise you will have to fall back on a gypsy jazz style rest stroke utilizing half rest strokes to compensate for lines that don’t follow the rules of only switching strings on swept string changes and upstroke escape on the ascended phrasing and upstroke escape on the descended phrasing, otherwise that is when the thumb/index will come into play for outside string changes for musically ascending string changes and inside string changes for musically descending string changes. But it seems like with Yngwie he only does the pull off thing on descended phrasing stuff. Joe Stump however doesn’t follow this rule, and uses more thumb/index to do the string change maneuvering on the descended phrasing.
I didn’t want to do this, but I will post this here for a bit to show how I might approach this short with my techniques.
This is what I mean so the red box indicates the start of the maneuver. I would do either forearm rotation or simulated forearm rotation on that downstroke. Then the blue box is the thumb flexion and extension move to get the pick out of the plane of the strings on a downstroke, which is against the rules in usx. The thumb flex upstroke is an escape stroke, and when I extend the thumb back out it shoots out differently from the flexion, putting the pick outside the plane of the strings. It goes out at a different diagonal on the downstroke.
So in reality the only time you really have to use thumb/index is on that one maneuver. I just think of that part of the combination of two phrases as faked fours sequence, using that upward ascend to force the outside string change because of the 1 note per string fragment that occurs.
This is just how I try to mentally wrap my technique around the inconsistency of shifting my setup position off kilter. You don’t really have to do the thumb/index thing until that very last downstroke before the outside string change. It will be a slightly different thumb/index motion, more adduction from the picked held abduction form, if done this way with little to no flexion or extension since the thumb will likely already be extended. And can even be wrist extension with no thumb/index movement, either way you have to get the pick outside the plane of the strings on that downstroke so there will be a motion that has to occur to do that outside string change, another would be forearm pronation.
