Re: Borescopes ??
My shooting partner and I occasionally have access to a Hawkeye. He is the one who actually gains access and I only take peeks with it when I'm over at his place a few times a month, so he does the grand majority of scoping and is the one with the actual knowledge.
The scope is valuable for correlating bore conditions with performance, and keeping track of those conditions over time. Cleaning consequences can be clearly determined, and we've eventually learned a lot about what is and isn't necessary vis-s-vis cleaning and accuracy.
As has been noted above, the information one gleans can be surprising and confusing, and can even be misleading, but any time information is available, it is always better than conjecture. Anyone can make mistakes and take information the wrong way, but there were lots of times we wished we had the scope when it wasn't immediately available, and I think that says something pretty telling about borescopes.
Greg