When Trek was syndicated in the early 70s, IIRC it was shown in my area only on WMAR, Ch.2. The cuts I remember from that era were sometimes the "less important" scenes (such as the Mexican Chili Peppers part from The Man Trap
). I remember first seeing that scene when we finally got a rooftop antenna to pull in the D.C. stations who cut their eps differently. These types of cuts didn't ruin the episodes, but removed some of the flavor.
Other cuts really made you wonder what was going on in the story. The worst of these was the teaser cut in Mudd's Women.
The episode began with a closeup of Lt. Farrell and his line "We're protecting him, sir. Won't be able to hold it long". The viewer had no idea what was going on up to that point.