It doesn't matter what the cause was. Federer had never made the final in Paris, losing to Monfils, Benneteau etc. He hadn't reached the final of IW since 2006 (lost to Baghdatis, Fish, Canas). He hadn't won Dubai since 2007.
There's no need to even consider the top 4. From USO '11 to USO '12, Federer failed to reached the semis once. That's the consistency he was missing in previous years, where he lost early in one of the summer tournaments, or in Paris or IW/Miami, or Rome.