i thought in-game resolution (in source games) doesn't affect mouse precision or 'cursor' speed?
also; not everyone who cares for 'proper' mouse responsiveness cares for it just to get better results in the game(s) they play, but plenty care for it just to get a more enjoyable (gaming) experience.
you could compare it with 60hz vs 120hz monitors. i know that plenty of people say that they don't, or barerly, notice any difference between the two (or they just don't care), but others will feel 'disgusted' by playing on 60hz screens, when they're used to 120hz.
some will play worse on 60hz, some will just enjoy it less. some don't care; good for them, less money and time to waste!
sound is another example. plenty of people care to get their sound the way they like it, but others will not/barerly hear any difference (or simply not care).
some will get distracted by outside-noise when using open headphones, some will just enjoy the experience better with closed headphones. some don't care; good for them, less money and time to waste!
investing time in these things could easily make you play better or/and make you enjoy your experience more. if either is true, and you care, then surely it's worth it to invest.
i don't see the need for bashing on people who put time/effort in getting the mouse and/or mouse responsiveness they want. because it's not about right or wrong, not even about agreeing or disagreeing. if you don't feel the same way, you might as well ignore threads like this.