I love this sort of nitty gritty article with good details. That said it would be more convincing if the writer followed the maxim of Chesterton’s Fence: if design-build is a better process than design-bid-build, why was the latter law created in the first place? It is almost certain that something went wrong when design and build were bundled.
They are making a claim that design-build is better, but when you look at the evidence it doesn't pan out any better. Design-build means contractors design something expensive (contracts are often cost plus some profit margin so the higher they can make the costs the more profit they get - if it is a fixed price contract they will look for places where they can build to the letter of the contract but obviously fail to meet the intent, then charge a lot for the change order)
