I can't speak for all of these jobs, but I can say that it took a bit of time to get back to Greased Lightning IV. And the MNK would lose it during a phase change for doing nothing wrong other than selecting being a MNK. Demolish (MNK DoT) always felt very lacking. I think the change they made in DT is pretty good. I'm still getting used to it though. But it boils down to using Demolish once for every two snap punch. So, it is essentially the same idea, just not a DoT.