Originally Posted by Torres
^ No movement at all. Absolutely none. Even if you pull them, they go back.
But then the polys I used don't show string movement at the point when I cut them out (6-8 hours).
Then again its probably less obvious given the typical tension I use, together with an electronic CP machine, and the denser pattern / smaller headed sticks that I use (95/18x20, 96/16x20 etc). It may be more obvious in something like an APDC strung using a crank but I'm not able to comment.
Ok, thanks Torres. I was thinking that if they were getting stuck out of line we'd have our explanation - less spin after 4-5 hours because the snapback effect stopped working. That the he strings are staying straight does not mean definitively that snapback is still giving extra spin, but it is suggestive. Maybe they have lost elasticity at that stage, in which case maybe the mains are snapping back but not with enough energy to actually put additional rpms on the ball. Perhaps your observation gives us another reason why gut mains/zx crosses might be better than full ZX - the gut mains wouldn't go dead and should provide great spin for the life of the strings.
It is interesting, though, that none of the RSI playtesters in either of the zx (16g and 17 g) playtests noted the spin decline you've observed. That doesn't necessarily mean anything though, as you are evaluating the string pretty thoroughly and criticly.