I dunno.It wouldn't be the IP holder who would have the problem of there being two different classes for these two different types of warrior... it'd be half of all the fans of the "Fighter" class that would be pissed off if their side of the class was the one that got made into a new class that was given a different class name and no longer called the "Fighter".
I doubt those fans would be upset if the Battlemaster subclass became a Battlemaster class. Or Warlord fans getting a Warlord, Warblade or Marshal class.
That was a different issue. That's splitting via fighting style not source.See: All those Fighter fans that could not accept in 4E that the "ranged fighter" concept was now meant to be done by taking the Ranger class, and that the "Fighter" was now only meant to be the 'tank' concept