Generally speaking, JP uses the RF and DF and leaves PF for learning parties. It would not surprise me if you were on the DC for Tonberry and were seeing PFs from English speakers using the NA/EU strats. Seeing as they were, apparently, using PF just as the players on NA and EU do.
I'd love a fight where it's required to use a healer LB3, just to break from the norm. Other than making A4S less of a pain in the ass.