Of course, the jury is still out on the "fix", but I am betting that if it is a PCM fix, it'll be something that may not limit hp/torque, as that would just open up another can of worms. If you think of it from a manufacturer's perspective, the best way to handle this midterm would be something that would limit a tuner's ability to change the tune. Of course, if it's mechanical, some type of differential isolator might be an alternative (I can't see Ford replacing vast amounts of subframes, but it's possible). It's also possible that it's something as simple as some bolts that weren't heat treated correctly. We can all speculate as much as we like, but that would be the most likely "fixes" IMHO.