Except, that the very thought has been posted by people across the net countless times since BackBreaker's campaign took shape.
They have to work together. Both games handled this the same way because they have to be. Having worked with several RTPe's, I'll say, if there is another way to implement RTP into a game where animations are driven primarily by motion capture, I'd like to see it and then be explained to how it was done.
Infinity is far less mature than Euphoria, and then I doubt Madden's legacy code helped the matter since its core animation system was/is already terribly flawed to begin with. They're basically trying to put a new coat of paint on a old rundown Ford Pinto, meaning it still looks bad and runs bad from an animation standpoint.
The one point we can agree on is that Madden's Infinity engine does a poor job of dealing with outcomes for limbs. It's very stiff and makes tackle collisions lose that realism that BackBreaker was able to produce in terms of how limbs react, at least generally since even Euphoria can't do it 100% of the time. But when you look at Madden's player models, you get the impression that the bone composition itself needs some upgrading. Limbs often seem to be locked at a certain angle. How bones are composed can really have an affect on it all.
But that's not what a lot of people post. A lot of people post online under the misconception that a real-time physics engine produces this on its own, and there are lots of posts over the years online illustrating that. Many people have gotten the impression that RTP means the end of "canned animations", but I again blame Natural Motion for that because before NM's campaign these things weren't said much by football gamers, if at all.
All RTPe's in mocap based games have to wait for a cue to interrupt the mocap cycle, so Madden and BackBreaker are no different in that regard. Based on what we see from Infinity however, it just appears that they've restricted the number of ways it can trigger moreso than what Natural Motion did with BB. In BB, it appears every tackle collision triggers RTP, whereas in Madden it's a toss-up and you will see the same tackle collision numerous times in the course of a single game. But there are pros and cons to both approaches. If Madden's core animations weren't already a disaster then none of this would be looked at as a big problem. They should've addressed the core animation problem long before venturing into real-time physics.