[somestag]

> There must be differences in how people perceive lag

Yeah, the only conclusion I've been able to come to is that some people are just more sensitive to lag than others.

If we're talking purely about enjoyment, then being sensitive to lag is nothing but a drawback. But from a performance standpoint, it's undeniable that lag has a heavy impact on gameplay. Your reaction time is constant from the time the light on the screen hits your eyes, so every millisecond you add to the pipeline from machine-to-screen (and from controller-to-machine) will strictly add to your reaction time. Sometimes even a very small increase in ms can change a challenge from "pretty doable" to "almost impossible" if the reaction time requirement was at the edge of your capabilities to begin with.

Whether or not this is "noticeable" depends on a lot of factors, including whether or not you've played the same game before on a less laggy setup. I think you're right that, given the same scenario (even the same skill level), some people just notice it more than others. Still, a part of me can't help but believe that it affects people's enjoyment whether they notice it or not.

I would love for a decent study to be done on this, because I think it has implications far outside gaming. Run an experiment where participants play a game in identical settings, except lag differs by small increments. At the end have participants rate their subjective experience, possibly along with their perception of responsiveness. My hunch is that even small differences in responsiveness would have a strong impact on experience, even if the participants don't notice anything "wrong."