I'm one of those players doing very good in the shooting department in AH.
Without tracers, I suck.
I tried it several times in my AH career, for extended periods each. And regardless of being noob or vet, I always had the same experience: When I shut off my tracers, nothing happened at first, I was hitting just about the same at all ranges.
But after 1-2 days a slow degradation started. And the more days passed, the worse my aim got. An this despite flying the same rides with same settings for several hours a day. Without tracers, I start to lose my mental sight picture somehow, even if I hit at first.
And after maybe a week (that's been like 30 hours game time), my ability to hit dropped to a third or even less the level it had been before.
So for short times I can switch tracers off, but I had never any real benefit in terms of hitting from it, but an ever accelerating decline, both by perception as well as very measurably by hit %. I absolutely do need tracers on to keep my aim consistent over time.