Operator error? Sure that's a possibility.
I admit that when re-mounting scopes on my bench, I too of have been guilty of Operator Error. As my electronics instructor would say way back in 1978, "Works fine when properly adjusted", or in this case, mounted.
For me, when I looked through the re-mounted scope with quick release ring and could not see the grid pattern in the collimator, I was baffled for a minute. Backing up to think through the problem, I checked my mounting to discover my front ring was clamped to the base, but the back ring was tightly on top of the rear base.
I have done the above at least twice. Operator Error. Guilty.
The above is from a technical type who started maintaining equipment as a farm boy, at 19 years old, I was a Corporal of Marines in charge of a Radar Course Directing Central fire control system ensuring ensuring bombs would be on target from 50 miles away. That was long before GPS and onboard fire control computers in aircraft. Later in life I managed fleets of equipment and resolved designed-in technical problems. Often the problems were resolved with published changes in procedures. We can all screw up at times.
Heck, the US Army published PS Magazine for decades which often provided guidance in the proper procedures. Why, because most equipment isn't "Soldier (or Marine) Proof! Let's face it, quick release scope rings are not hunter-proof! Sometimes Keep it Simple, Stupid (KISS) is a very good rule. Whatever process and mounts work for you!
