I was taken to task in an earlier post for using power (reverse) rotation to remove chucks on lathes (that post and my answer to it were subsequently removed from this posting) the postings were civil, but not in line with the spirit of HM, and I was not sad to see them removed.
I would however defend my use of reverse to remove chucks, but would say that the practice should be used only on larger machines, where a crescent wrench and mallet are not about to do the job; on shall lathes such as most of HM people use, it is not necessary, the chucks are usually quite easy to remove, and on my 9" Monarch, I use the wrench on the chuck jaw and a lead hammer and usually it is easy to get the chucks broken loose; on my 19" Regal that is not at all the case, and I use the back off under power with a wood block on the back ways nearly always.