ok the question in the title is a little obscure, so I'll clarify what I'm asking. At endgame I tend to see the same type of classes in Abyssea - nin, whm, blm, thf, blu, some other random dps which tends to be either a mnk, drg, sam or a war, and sometimes I see people soloing as dnc, bst, or smn. I never or rarely see in Aby a cor, sch, pup, pld, brd or rdm, and as for the dnc, bst and smn they're always usually by themselves.
Someone commented a while ago that book burns means that no jobs are left out so that even bsts can get levels with ease, but once at endgame almost half the classes are either rarely ever seen or struggle solo. What is the point in getting a brd to 95 if in the end the only use for it is subbed by a blm to provide black magic and song procs? Gearing up a brd through playing as another class in Abyssea just seems totally pointless if a geared brd has no place in Abyssea. Is there a point I've missed?