Yeah the whole “dehydrate the fuck out of yourself to make your muscles pop a bit” thing is so irresponsible. Jackman pulled the same thing for the opening prisoner scene in the Les Miserables movie, which was doubly irresponsible because he had to sing, and being dehydrated makes it really difficult to sing well, and potentially puts you at risk to damage your voice. I think I’ve seen interviews where they spent like several hours on that scene because his voice kept breaking. So not only was it super bad for Jackman, it also wasted the rest of the cast and crew’s time.