HA in the dictionary or industry sense would make me think of a product like VMotion. Microsoft's support statements say they don't support hypervisor-based "high availability or migration" and personally I would interpret these in the dictionary sense.
In other words, and basically echoing what others have said, VMWare decided to rename their "VMWare HA" feature, would it be ok?
Hardware vendors have features that allow servers to automatically power back on after a blue screen or accidental button push., which is almost the same.
I do agree that its redundant with the DAG model and more complex, but then again I can think of situations where cluster failovers didn't quite work for some random reason and it would have been fine if the original server just came back alive.