I think it's just your imagination, I mean, if You believe you suck at 1 and not the other then your mental state of mind during the game is already unstable, and vice versa... Get what I mean?
Yet the honest trueth of the fact is that it's not that you suck at 1 vs the other, it's just that maybe your applying the same ruiles, you use to achieve such high goals in Mtts, in Ring games???? Does that make sense? There-fore hurting your game (Cuz rings all-together are'nt the same thing, as Mtts)...
Hope that makes Sense