Yeah, then he fixed that mistake by trading him to some schmuck for Iwakuma. Then he traded Iwakuma back to that schmuck for Betances and Clint Frazier.
What do the Rockies even want McGee for? They're nowhere near the point where their pen matters, and McGee is an injury-prone reliever who's value is pretty volatile.
The two rotations combined are Richards and a bunch of garbage. You can't really argue that Colorado's garbage is better than LA's by enough to make their rotation better overall.