Using acceleration in Quake (3) is insane... you need awesome aim to play that game, and you won't get that aim with acceleration on
Being good in Q3 depends 50% on movements and 50% on aim (according to the very scientific study by me )... if you don't have the movements, you're toast. Same goes with the aim.
Check this vid; it's really old (2002), but it demonstrates rather good what I am talking about... look at fatal1ty's aim with the lightning gun
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