If someone can do two-way economy (say a 3nps ascending and descending scale), does that mean they can also do USX and DSX lines with that same form, since you have to be able to do an efficient tremolo in both orientations? Or maybe not, because your tremolo could be a trapped orientation with no slant (or is this incompatible with economy picking?)
And if so, what are some players that can do this, so I can copy them?
I could be wrong but I think 2 way economy is more trapped than anything. There really isnāt DSX/USX because thereās no escape happening. Itās more just slanting to help the pick glide smoothly and not get stuck.
I know Iāve heard Troy say many times that Frank Gambale, probably the poster child of 2 way economy, does lots of primary DSX with descending economy. So in that case there is some escape happening.
One thing weāve discussed in other threads is the idea of being able to do continuous USX or DSX. There are players who are primarily DSX that can do some patterns that require an escape after an upstroke but this is sparse. If you had them do 2nps playing that was continuously changing after upstrokes, they probably couldnāt do it.
I think the only player that comes to mind who can do 2way economy and can do continuous USX and can do continuous DSX is (drumroll)ā¦Troy 
I could be wrong but I think 2 way economy is more trapped than anything. There really isnāt DSX/USX because thereās no escape happening. Itās more just slanting to help the pick glide smoothly and not get stuck.
Yep, very well could be. Maybe the more ābiasedā in one direction the orientation is, the harder it is to do two-way economy.
I know Iāve heard Troy say many times that Frank Gambale, probably the poster child of 2 way economy, does lots of primary DSX with descending economy. So in that case there is some escape happening.
Yeah, my DSX escape happens easily with descending economy, and I can do a USX helper motion. Unfortunately continuous USX doesnāt seem to work with my form unless I adjust my pick grip.
One thing weāve discussed in other threads is the idea of being able to do continuous USX or DSX. There are players who are primarily DSX that can do some patterns that require an escape after an upstroke but this is sparse. If you had them do 2nps playing that was continuously changing after upstrokes, they probably couldnāt do it.
Yeah, a good test for this is going up a 2nps pentatonic scale with USX or DSX and then doing 3nps at the turnaround so you go down with the opposite orientation. I can kind of do it but my USX feels choppy and then the DSX is smooth sailing.
I think the only player that comes to mind who can do 2way economy and can do continuous USX and can do continuous DSX is (drumroll)ā¦Troy
Haha, yep. I appreciate the advice now about sticking with whatever technique you stumble on first. Learning new motions is a very finnicky and difficult process. At least my stubbornness has given me a USX and DSX form, but I canāt combine them seamlessly. But thatās just me being greedy
Just to add another wrinkle, when I do economy picking there is no slant and also no escape; the hand just plows through the strings with arm-tracking and when I start alternating again the escape comes from DBX rotation. At least I think it does . . .
I practice two way economy now and can do both escapes with some minor tweeks to the āslantā It doesnāt have to be a trapped motion. I actually find it much harder to do a trapped motion!
Itās kind of cool as it gives a lot of options, but learning to control the timing and dynamics are the biggest challenge, for me.
Edit, having said that, itās unlikely Iād try change form in the middle of a phrase!
Right I guess thatās what I was getting at. I think 2 way economy is a different animal than the now partially (mostly? lol) deprecated concept of ā2 way pickslantingā from the Antigravity seminar. For example, if you were going to play an ascending and descending scale with your economy picking, wouldnāt you have āno escape at allā? Or do you have a different system that incorporates pulloffs into descending phrases? If the latter, Iād consider that very much a one-way economy (sounds like travel ticket lol)
I can do a scale up and down but seen as I donāt need an escape, my form might be slightly different.
For two decades I was an economy picker. I didnāt know about one way systems back then. Knowing about it now has opened up a lot of options since I started practicing economy again.
So I try to practice phrases that are one way, and also ones that require sweeps in both directions. Iām guessing my form alters slightly to facilitate this, but Iāve not really looked too far into it. Iām still in the R&D stages of my return to economy picking 
Sorry if this was already touched upon, but also some phrases kind of back you into a corner in a sense that even if your intent is to āsweep changeā all the string changes, youāll HAVE to have some escape at some point. Sometimes a slur can cancel out the need for the escape, sometimes a slur just gives you more time to make the escape.
Sometimes you can change note locations to avoid this, sometimes you canāt, sometimes you change the phrase to work with the technique, sometimes you donāt.