Well, this season he's had 3 starts deemed good by xFIP, one at 2.65, another at 1.70 (the 9 K game) and another decent one at 3.21. But then he had the horrawful 8 walk start and that kind of skewed the numbers.
IMO the only way Happ is more useful than Morrow is if the latter gets injured again (which is a very real possibility), but to say that a healthy Morrow isn't the much better asset is pretty far out there.