Did Nadal ever come up with a winner/risky shot at mp? I don't think so. Nadal's game is based on safe moonballing, so naturally his tennis is less error prone than others.
Federer represents a completely different gamestyle thus makes more errors even on big points.
How you can expect Nadal to mishit if his ball placement and net clearance is rather laughable for a player of this sort?
irrelevant points, how clutch you are on big points does not relate to how you win, but just the nature of winning them at all...