The second real example to pop into my head is Tires. (Sorry if American doesn't carry over...) You've directly implied that it makes sense for Chrysler to make better tires than a company that doesn't make cars. But Firestone, Goodyear, Michelin, and Interstate seem to argue against that. N.B., looking at the WPlist of tire manufactures I don't recognize that any make cars. The idea of sub-expertise is not very realistic. I considered whether it's usually the other way around that the leading producer of a sub-product of turns into a notable end-product producer (Film Producer Kodak ends up making cameras), but that is also not an indication of expertise. (Kodak cameras were never top of the line, afaik. I guess, (ironically?) they were a low-end leader because they couldn't compete with the best ones? lol)
You have made some very good points and I must say I agree with you on them.
