To be honest I have not read the whole book. The first two sections were the most valuable for my job, because they described the behaviors necessary for effective communication from design to manufacturing. Keeping those behaviors in mind while still doing high-level design activities made for a smoother transition. Specifically - SBCE or Set Based Concurrent Engineering.
I think to successfully design derivative vehicles - or any other product - its essential to have some idea of the longer-term product road map. E.G. how a Camry platform can beget a Highlander or Lexus IS etc. when designing the very first car.
One debatable point, and one that I often challenge my engineering peers with, is that Toyota usually comes in toward the bottom of informal styling ratings. Lexus too. Whether this is a result of the superior development and manufacturing process is unknown. “Looks ugly but will drive forever”.
But yes, I think its worth it still. Most of my career has been in commercial/industrial products but I’ve spent some time in FMCG (soda bottles) and the behaviors detailed in this book could have been applied to fast-moving industries as well.