ETA: like they could have made Kirk go really insane then tried to commit him and keep him.
It always seemed to be a well-executed bad idea. Or maybe it was just an underdeveloped idea - the concept of mental illness/violent crime in the future had some promise, but, ultimately it was about a person of authority abusing institutional power and those under his care. Part of it was, in the 60s, the Nazi atrocities were still fresh in the public consciousness, and Adams' mind control experiments kind of smacked of that.
However, tough to believe when the guy had spent his life treating people would "break bad" in this manner.
However, I thought the acting, particularly of Woodward (Van Gelder), to be superb. (Woodward will return as a starship captain in "The Omega Glory".)