Triumph decided to use this swirl bowl (my term for it) because it's cheap and easy and effective.
That just about describes a perfect design.
Mates son has just returned to the UK after 3 years working on design at one of the major German car firms, and cheap, easy and effective is what they work on for there new car design.
My favourite engineering axiom is:
"Good, fast, cheap. Pick two."
Until recently I think the Detroit bunch included "acceptable to the lowest common denominator" as a choice, and tended to marry that with your last choice, which is what got them into trouble.
They were answering to the investors first and foremost. Many years ago I worked with a guy who worked for one of the big three and he said that if they had a part with too low of a factory warranty repair rate they figured it was overdesigned and look for ways to lower the cost.
So you are right, they were working ro the lowest acceptable quality level. And why not? What is the buying public going to do? Buy Japanese???!!! Ha, that will never happen.
"Don't think of them as problems, think of them as opportunities."
"OK, I think I've hit an insurmountable opportunity!"