I am on the developer side on a project with a design-build contract with a major contractor. the architecture side and contractors are pitting against each other internally, because the architect is still liable for his drawings being correct, and the contractor is still liable for the work being complete to the contract documents. Seeking to align efforts to minimize detailing costs is a recipe for very costly mistakes down the road when something doesn't satisfy fire code, building code, ADA, insurance, lender requirements, hotel brand standard (in my case). Theoretically, I suppose you would only see streamlining if the Owner-Architect-Engineer-GC-Regulator was one entity, like a government maybe.