I actually agree with the concept of making all classes multi-role and I think it does have a lot of potential, Rift did something like that where they made every single class capable of tanking, melee dps, ranged dps, support healing/dps, and healing with the right build. It also opened up options for folks that might not have liked a class, I didn't like Rift's mage for example but once they added a melee dps spec and a tank spec? I love it now.

However, that does create an issue of having a lot of different builds to balance and I don't think SE would be willing to take the time to do that. Their design favors a very structured system with a single class identity and while I actually like that aspect, I can understand others might not. I can totally understand that someone wants to dps with a greatsword or play a ninja tank or heal as a paladin but that doesn't really fit with SE's vision. I think in this regard Wildstar made the right decision by making every class have two different roles they could fill from day one (dps/tank or dps/heal) and it would be more difficult for this game as it would require a lot of restructuring. Another part of it, is that with the whole armory system, the devs encourage you to find a class you like for a role, want to melee? Try mnk or drg or nin. Want to heal? Scholar or White Mage or Astrologian. Keep going until you find something you like.

That being said however, I hope SE doesn't rule out the idea entirely. I think maybe adding a secondary role to each Job and letting us switch freely between them at will isn't a bad idea, especially for solo play. For argument's sake, let's pretend everyone has a dps build and they release a new set of main story quests, I'd love to be able to put my drk in to dps mode and bring out my chocobo to speed it up before switching back to my tanking build to queue once I reach whatever the dungeon we have to complete for the main story completion.