Definitely a cool topic. I do like how 3 Nightforce optics ended up in the top 6 for optical clarity. I'm not sure how I feel about 6% of the total score being based on available... Especially when 6% separates 1st place from 6th place.
Other than that, it looks like a well done and definitely good to see someone take the time to experiment with these optics.
As far as being able to use the optic at long range, 600+ yds. IMHO, and from my experience shooting to 1200 yds at steel, there's nothing at 600+ yds that cannot be evaluated with proper tools and techniques. When he tested optic travel and accuracy to 20Mil, that's enough elevation to push my .308Win with 175 Federal GMM to 1325 yards at 3500' at 50 degrees. Optical Resolution and optical clarity is not going to change at 600yds vs 100yds. Anything beyond that is just paralax adjustment which is possible on each of these optics.
Not all testing was done indoors, Some of the optical and mechanical tests were performed outdoors such as FOV and Adjustment testing. Optical quality testing was done indoors so that there would be no change in lighting conditions between the 6 testers testing the 18 optics in three tests. I'm sure this was an exhaustive process and took several hours possibly across multiple days. This IMO is the only way they could have accurately and honestly tested 18 optics with multiple people in this depth, without changing lighting conditions. The USAF low contrast line test is designed to test low light performance of optics in a controlled environment.
I also wish that he had an FFP Nightforce ACATR to test, with the new reticles and FFP option, this should now be in the top five. I really like the look of the new 4-16x42 ACATR F1. This might be my next top shelf optic, if I can convince myself that it's $1000 better than an HDMR...