At www.savageshooters.com, they did a comparison of several scopes that was reasonable, but flawed from a scientific standpoint in several ways, but was a good attempt at trying to compare scopes. I have lobbyed frequently for someone to do double-blinded testing on rifle scopes. This could be done with scopes from various manufactures within the same specs, such as erector power, objective lens size, tube size and variable range. Now the test for one set of scopes of say 3-9x 40mm, 1 inch tubes, without an AO, would not apply to the remainder of scopes in the line-up of the other scope manufacturers, but may give a clue. Tests, similar to those done with camera lens may be employed, in addition to those unique to rifle scopes. Focus is correct, it is mandatory that if you want to pick the best scope out of several you are comparing, in say a certain cost range of range of features, you have to look through the scopes side by side. Opinions of other people matter, but it is the cumulitive opinions that matter the most. Unfortunately, there are alot of people that are brand loyal and no matter what flaws they have encountered with their scope or whatever product it is, they will not disclose those flaws and stand by there product. Alot of people on this website feel that the quality of Leupold is not in line with their inflated pricing or their competitors at a much lower price, while there are others who believe the price is worth it and the quality is just as good. I have never owned a Leupold, because I believe they are overpriced and the ones that I have looked through, while very good where not any better than what I own. I just posted a new topic regarding a new Swift scope I purchased, as they are now made in the USA, while previously made in China. I have owned many Swift scopes and they were great. But, when China became a problem, I refused to buy anything from that country, unless forced (you know, some things you can find, are only made in China). I was considering bitting the proverbial bullet and buying a Leupold, just to see for myself how they performed, as looking through a buddies is not a fair comparison. But, the affordable line, VX II, does not even have finger adjustable E/W curls. Yes the Swift scopes have finger adjustable E/W dials. You have to go up to the VX III to get that, which took me into a price range I did not want to encounter. The Sightron SII 3x9 42mm is a fantastic scope and was going to get it, as I have other Sightrons, but I just wanted to check out the new Swift.
Overall, to summarize. Double blind testing is possible, but would be somewhat difficult and expensive, similar to comparing 2-channel stereo equipment and knowbody in the industry wants to do it, because they are afraid of the results.