A friend of mine who works at GKN said that for a while Doug Shephard was coming in with nuked SRT-4 halfshafts after every rally. They eventually came up with a Doug-proof shaft, and apparently it's in production.
I know that at Ford, "technology transfer" is important with any racing program. The desert teams send back junk uprights and such from their trucks and pre-runners and Ford sends them back revised designs to try before they put them in production.
In my latest contract with Mazda, I am obligated to share everything with the company. And they are more interested to hear it...it seems there is a better connection between us and Japan than in previous years.
I even got flexural modulus info on the body shell from Japan before we started on cage design.