Yes, pretty much. But again, to be pedantic, because it seems that’s inevitable (!), I wouldn’t think of “two way pickslanting” as a term describing a motion. The pickstroke is the term that describes the pick’s motion relative to the strings - either the angular kind, aka single-escaped, or the curved kind, aka the fully escaped pickstroke. And beneath that you have the actual body movement itself that creates that pickstroke, be it forearm, or wrist, or whatever. Those two lower-level layers are more concerned specifically with motion.
What you’re describing from that point onward though, yes, totally. In a two-way pickslanting type of phrase, you’ll start out making the single-escaped pickstrokes, then reach a point where you’re going to need to throw in a curved pickstroke. You might then make single-escaped pickstrokes again for a while, and then throw in another curved pickstroke. This would be the case if you were to play, for example, a compound type phrase where the ascending part uses one pickslant and the descending part uses another. There would be one fully-escaped pickstroke at the switchover point. The entire compound phrase is something I would describe as a “two way pickslanting” phrase. Either half of it, I would describe as one-way pickslanting.
In the classic “primary pickslant” scenario which we see in scale playing, you start out with single-escaped pickstrokes, and then throw in two curved pickstrokes back to back during certain string changes. Same general formula as the hypothetical “ascending/descending” phrase we just outlined, in the sense that the line still contains a mix of pickstroke types. But in this case you’re clustering the fully escaped strokes together in units of two. And since there are lots of people who appear to play this way, giving this particular “style” of playing a name seems to have some usefulness in describing what we’re seeing.
That’s the concept - naming things so we can refer to them and know what we’re talking about. Hopefully we’re doing more good than harm here!