I read but eventually is so difficult to accept I don't agree what the OP say.
Why can you define yuffie a ninja? Because she equip a shuriken and roleplay a ninja? Why can you define tifa, because her "attack" button uses punch? for their costumes?
Don't judge the book by its cover. If we are talking about clothes or better, textures, ok. but how you can read from his reply, we are not talking about that.
I don't remember Tifa dealing more damage with punches than Aerith for example.Archer =/= Ranger. Why? Well one...it's an archer...
Pugilist =/= Monk. Why? One...it's a pugilist. Monks could also use their feet. Pugs cannot. Monks were spiritual and could use Chakra. Pugs are brawlers...
Black Mage =/= Con or Thm. Why? Neither of those say "Black Mage." Black Mages can't use healing spells, most buff spells and can't use light based spells. The opposite goes for a White Mage. Also, the current spells are too under powered to be focused on a specific job. Black Magic Con =/= Black Mage in terms of damage. White Magic Con =/= White Mage in terms of buff power and effectiveness.
No one force you to equip an healing skill, and you can raise only int and piety, to deal more damage than a healer (who need to raise mind). And healing from Barrett or Auron was strong as from Aerith or Yuna or Lulu.