It's fair to say GM did copy it well in the Saturn experiment, but failed to bring it fully to the whole company. VW can't help themselves from making complicated things. Honda is onboard, but Nissan still thinks in terms of supply side and will churn out garbage to meet next quarter targets.

That being said, Tesla went back to early Ford for the full top-down flow system - and it's working for them. So while I love the TPS system and use it in my company, I'm willing to keep on learning.