I think Tony Dungey made a good point of this during the Washington Tampa game when Sims' touchdown catch was reviewed. He got both feet in but in super slow mo you could see a slight bobble of the ball. Only at super slow. He then said for the past 100 years in football this is a touchdown. Because of technology and being to see something minute does not make it so. The officials came back and announced it was indeed a catch, as it should have been, as it has been for the past 100 years as Dungey said.
The same holds true to Davis' catch. Perosnally, I don't think the technology should be used to pick up such subtle minutiae, but rather for to prevent glaring mistakes that were missed. Like if a foot was in or out or perhaps something like a knee that wasn't down when the ball came loose for instance. Which was fairly obvious to 30,000,000 people watching the game.