I think Lewis does have one problem that Rosberg had last year. He has to put more strain on his material. Rosberg had the better starts and could basically cruise home in engine saving mode. Last year that was usually Lewis, while Rosberg had to fight throught the field and probably had to run the engine in non-detuned mode a bit more often and consequently had more problems. Then there is also the possibility that this year's engine is a bit more on the edge, reliability-wise and Lewis' generally harder driving style might come into play.

But that's just my theory. Probably a lot more plausible than the 'he got crap mechanics' conspiracy. We shouldn't forget that those mechanics still knew how to do the job when Rosberg won the last three races last year.