Playing with FPS over 60 is an advantage over FPS at 60, but discussing that is inconsequential as it makes no difference under the server rules provided you don't go over 155 and jitter. 60 vs 120 is not what this thread is about.
Having the mod limit FPS is a good idea but evidently it doesn't quite work as it is now. The rarity of jittering and the fact it's always dealt with appropriately doesn't justify giving people issues with screen tearing or whatever else. If it can be fixed to do its job without causing issues then that's great and I'm all for it, but jitter is so rare it's not worth keeping a built in limiter that negatively the game experience for even one person.