Hello! I know this is a necrobump but had to reply with my results after using the methods explained in this thread.
I was reading this thread thinking leveling parry might take a while... So i went out there with a terra staff, some montagnas and a prousse ring with 50% pdt as NIN/dnc, 'borrowed' some mandies about 15 of them EP off into a secluded corner where people usually don't traverse and after 5 hours I went from 270 skill to 401, I was shocked I procrastinated this long to lvl it ( Even with the update coming to make it easier to skill it up, it didn't take long to get to a respectable parry level ). It slowed down after 400 so I killed some mandies until they went DC, pulled 15 of those and currently at 412 after 45 minutes.
I don't think there is any reason not to do this if you're a career nin now o.o, kudos to those who contributed to the thread, it really works well!
Edit: Just capped at 417 base within the hour O.O woooooooo