Guidelines like RAIL are popular in the web performance community. They often define time limits that must be respected, like 100ms for what feels instantaneous, or 1000ms for the limit of acceptable response time.
Prominent people in the performance community keep telling us that there's a lot of science behind those numbers.
I've always been skeptical of that claim, and earlier this year I set out to find out if there's any merit to those numbers by doing an extensive literature review of web performance perception academic research. Here are some of the findings from that project.
If you follow paper citations, some classic papers keep showing up as references. And in the world of web performance, two