We used no volt meters, dark rooms or any other fanciness to test out these gaiters. We basically just threw them on and hit the trail, glacier or scree field. We often wore multiple pairs on a single trip, different gaiters on our feet, and tested them with a variety of footwear. In short, we spent a lot of time putting on and taking off our gaiters and shoes, intentionally tromping through the muckiest parts of the trail, and splashing our way across shallow streams.
In truth it was all good fun, and though we had to send our tennis shoes through the wash a few times and take a scrubby sponge to our mountaineering boots, it was all worthwhile. We did get a little high-tech on occasion when we wanted to test the waterproof of the gaiters. This high-techness consisted of holding the gaiter up flat and placing it under a running faucet for several minutes to see how the material held up. All very scientific, and it genuinely demonstrated which gaiters actually had waterproof materials.