Its not complete crap, but I think that you have to change one thing at a time. You're right in that putting 0 rear wing at monaco, but with original gears, you'd be gear limited, but you'd never do that really...so small incriments of change you will notice, like with 2 more on front, one more on back, you may be able to carry more speed thru lower speed corners, while gear ratios would remain unaffected, as would straight line speed.
I dont think I made it that clear, but basically its not ideal to change one thing at a time because you're always affected by the other settings, but at the same time, changing wing, gears and springs together would be bad, because if it was slower, you'd have 3 variables to work through, not one. Personallly I stick to the original setups, if you know the tracks well enough, you can win at ace mode most of the time - and its quite a challenge, though at the samme time there's nothing better in gp3 than spending a boring hour on setup, then beating your best lap by a full second, makes it all worthwhile
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