Where did i say that playing games on a 120Hz monitor increased the framerate for the game? All it does is increase the amount of frames my computer can display. Now my Computer can display upto 120Fps without screen tearing. It's not magically gaining me any additional FPS.
& why oh why do people mention refresh rates? Fps & Hz although the same have totally different effects, if you have a game running at 30fps on 120Hz TV the game doesn't became 120Fps,
I'd agree with you expect your point only really works with a 60Hz TV.
the thing you are doing is messing up the framerate by increasing the speed the picture is refreshed which which is fine when its stable especially locked at 60fps but if ain't it sometimes misses frames or in the case of framerate rates dropping missing loads of frames, thats why you can notice it worse then others because it is worse, and I thought you of all people would know this.