The fact of the matter is if that DC had really and truly rebooted the DCU after Crisis (or Zero Hour), Hypertime wouldn't be necessary. Of course, that's easier said than done, and as such you're better off having stuff retconned into Hypertime that ignoring it altogether.
So anyways, yeah, not a big fan, but noone's really abused it yet. Of course, I'll change my tune once they announce an All-Star/DCU Superman teamup...