There's no winning here (as with absolutely everything in FF), but I think reducing new player confusion is a worthy goal, and that's why the single shotgun was removed. The role being emphasized is just a side benefit.
EDIT: I really suggest everyone watch that video I linked above, it's really eye-opening. He goes from class to class and uses the single shotgun on
almost all of them for
almost two hours and never gets a clue. He might be an exceptional outlier, but it seems silly to keep the single shotgun if there's the potential for new players to get such an inaccurate view of the gameplay.
EDIT#2: Created an issue about the model being confusing:
https://github.com/fortressforever/f...ver/issues/149. If that gets implemented, I'd have no problem adding it back to the pyro.