I wouldn't say it has been anti-hype as such. Obviously WWE is going to try to make Cena look better. He is in Miami at Mania, the odds are stacked against him, it's The Rock's home crowd. I think regardless of what Cena has been saying or ways to try and make him look better/make The Rock look worse (e.g. the wrist notes) the crowd will be against Cena. But the fact is Cena is the top guy, and they need to make him look as strong as possible going into the match at Mania.
As for a physical confrontation, one is not needed in the run up to their match. Let the promos do the build-up, leave the physical confrontation where it belongs - in the ring at Wrestlemania.