I think the author’s use of a 500Hz display covers up or minimizes a lot of issues. It’s really easy to look at this data and say 8ms click to flash is fabulous even though he has an config that does 4ms.

A better way to interpret this data is to normalize by the vsync interval or the swap chain depth. The slowest config is 2 frames slower than the fastest. At 500Hz this is 4ms extra which is likely imperceptible to everyone but elite pro gamers. At 60Hz this is 34ms extra which is pretty noticeable to even casual gamers.