Didn't really feel like making real thread about this because I don't feel it's complete enough and don't have a real intention to complete it, but:
I've been dicking around with Restraint lately. My first impression was that SE probably just meant TP when they said, "Enhances your weapon skill power with each normal attack you land." but it looks like they were serious. By the time I get to doing the tests below, I know that it affects Magic WS damage already from dicking around with it on crabs. It already does something as early as 104 TP, though the nature of K-club and the Crab's Shell move prevented me from getting more exact than that.
Club of Trials / K-club with Shining Strike on Gobbue in the tree
300TP Shining Strike - 393 damage
300 TP Shining Strike with Fresh Restraint on - 440 damage
So at least part of what Restraint does affects either fTP or WS damage, because it works on a magic WS. At this point I'm liking the story because 440/131 ~= 3.35 fTP, so I'm thinking maybe it's +10% WS damage or fTP or something. So I go to replicate it and check if it's number of hits or TP based.
Repeat Club of Trials / K-club with Shining Strike on a Gobbue in the tree
300TP Shining Strike - 393 damage
300 TP Shining Strike with Fresh Restraint on from 0TP - 451 damage
Weelllll then. This just got infinitely more complicated because the one thing I have a shitton of with K-club is extra hits. Going to be impossible to narrow that down to an Hit : Damage increase relationship, but I can at least solidify confirm that's what the relationship is:
300TP Shining Strike - 393 damage
300 TP Shining Strike with Restraint on from 0TP and extra hits past 300TP - 499 Damage
So it keeps going up with the number of hits you do even past 300TP. That's cool I guess. Does it reset when you use a WS?
300TP shining Strike - 393 damage
300 TP Shining Strike with Restraint on still from the last one, new 300TP used immediately - 440 damage
That'd be a yes. I get 6TP/hit with Club of Trials/K-club, which means it takes me approximately 50 hits to get to 300TP. I'm getting approximately damage+50 on my WS (less, actually). Please tell me it's not so SE, please.
So, on the next Gobbue I engaged it swung and pulled back to a save spot, turned around, Activated Restraint, and got incredibly lucky.
191 - 271 - 4 hits got through (1 attack round) before I activated Restraint (I was hit 4 times)
191 - 273 - (I was hit twice)
You'll notice there's no control. I haven't hit a Gobbue that doesn't take 393 damage from a 300TP Shining Strike at this point, and I don't think it exists. Gobbues here all seem to have the same INT. We would predict about 260 for these values without Restraint on.
I don't know, this is kind of where I want to end the testing. You could continue the testing to differentiate between +WS Damage % and fTP if you felt like it though, because:
Damage = (( Lv+2+WSC ) * fTP + fINT ) * Resist * Elemental Staves * Weather * MDIF * Magic Damage Adjustment
Simplifies to: Damage = (( Lv+2+WSC ) * fTP + fINT )
So fINT was about 15 for me. That's . . . a pretty crappy fINT (but I'm WAR, so I guess I can't be picky). Still, this would lets you differentiate between +WS damage% (which would affect everything) and WSC if you minimized (Lv+2+WSC) and maximized fINT (8+dINT/2).
Now, I suspect that it's actually Weaponskill Damage +%, but my reason for suspecting that is due to one of the weirdest weaponskills in the game, Moonlight. It restores 62TP at 100TP regardless of Restraint. It is affected by TP, though I can't promise it's affected by fTP. If I was making a formula for Moonlight's MP restored, it would be:
fTP*(Club Skill/9 -1) = MP Restored
fTP @100 = 1
fTP @300 = 2
Restraint doesn't affect it, but there's no way to prove that the "fTP term" I have in there is actually "fTP" as we know it, because it's such a weird goddamned WS and it isn't aligned with any WS gorgets.
tl;dr: There's no obvious reason to not use Restraint anymore that I know of. However, if the benefit/hit doesn't scale with Delay or isn't directly related to number of Attack rounds, this JA is barely worth the 2 second delay it takes to use. Keep in mind that it was taking me ~50 hits to get to 300TP at minimum for a ~10% increase in damage. It would be something like +1% WS damage with a GA at 100%, potentially only to the first hit.
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