Of course, where gathering this sort of data _is_ useful is diagnosing and fixing real latency so it obviously has merit. I just think it's ok to lean on taste and experience for most things UI/UX, including latency.
Another point, by couching the comparison in a less technical form (for example, rating a configuration/setup out of 5 stars or some similar approach), it protects from being "too methodological" during testing and data-gathering. One possible issue with the author's methods is if there are degenerative cases that are common in the day-to-day experience of a given configuration, they are unlikely to be present during the precise test that they have setup.