Hi 
all 
I noticed whilst watching the Brandon Ellis clip that he has a fairly obvious DWPS but keeps his thumb/hand relatively close to the strings, has anyone else noticed this?
I don’t recall seeing this in the primer but could be wrong. Anyway, it seems useful as it lessens pick resistance quite a bit 
I would view these things as more a personal taste than anything. Sometimes a little bit of string resistance isn’t that bad honestly especially for feel based techniques like sweeping and economy as it might help with the timing of the string transition and articulation of those techniques. It’s all a balancing act.
Well, there’s this Martin Friedsomething guy…
So not impossible, but it can impact your escape possibilities and therefore note choices. I’d prefer a grip that reasonably allow for both slants, even if you only ever use one at all times.
With a compact trigger style grip and edge picking, I find I don’t need much of a slant in the direction of the sweep for it to feel smooth.
When trying the same thing with an extended grip, which gave less edge picking, I could feel the arm flip flopping.
So there is a relationship between grip used, edge picking amount and slant.
That’s just my experience with this sort of thing