Board Thread:Questions and Answers/@comment-33935463-20180426192324/@comment-4148373-20190315041254

Q6w7e8r9t0 wrote: No, I meant time skip, or time erasure if you prefer. I was discussing the actual canonical ending to part 5. And while Diavolo gets to perform the "cause," it's quite obvious that it's undones beforehand as the time skip itself never got to actually happen at all.

But yeah, as far as TWOH vs GER goes, it's all speculation. I doubt they intended it to have an explanation to begin with. Uh...nope, pretty sure it happened. Yes, the effects of the skip, including any sign of it happening, seem to have been erased. However, if it "never happened", GER would never have punched Diavolo. Which then means the skip happened. Which means...well, I think you get the idea. Part of the reason why explaining GER's power as "negating effects" works so well is that it removes the potential for paradoxes. Also explains why Diavolo got looped significantly better.

Agreed on the second point, though. The game devs probably didn't bother to think too hard on it.