I really, REALLY question their "design" process in many cases. IMHO most of the time it looks like they gave the production guys the stuff and told them to install it with no drawing, design or direction. Not to mention total lack of oversight and quality inspections.
I have worked on a variety of projects over the years, while input from the guys that do the actual work is very important, you usually DON'T give them free reign when it comes to doing layout and solving issues, if you do the results are quite often spectacular failures. Not to mention that fact that I seriously doubt very many of the assemblers at Keystone/Dutchmen would be considered skilled labor.