Those have to happen if Musk has any intention of fulfilling some of the things he has said so far. He is repeating over and over that one of his goals is Mars, and while Falcon Heavy can carry Martian payloads, it doesn't quite cut it. This and the other things that he have been mumbling are strongly suggesting that he intends to work on those (or similar ones) once he gets the opportunity.
That doesn't suggest they have any need for a heavy lift vehicle. Quite the opposite in fact, Musk probably envisions a spaceflight architecture based around the reusable Falcon 9H and dragon-derived orbiters. There isn't a whole lot you could do with a single HLV that couldn't be more efficiently accomplished with three MLVs, especially if the smaller rockets are reusable.