In 2011, design–build continued to gain ground as a significant trend in design and construction. In March 2011, industry consultants ZweigWhite published "Design-Bid-Build meets the opposition". In it, they suggest that while Design-Bid-Build "still rules", the traditional approach is losing favor as "alternative project delivery methods threaten [the] design-bid-build model." While not referencing the architect-led design–build approach specifically, the article states that D/B already accounts for 27% of projects, according to their 2010 Project Management Survey and goes on to argue that, The emerging trends in delivery seem to point to a return to the primordial concept of the masterbuilder, as exemplified by D/B and IPD [Integrated Project Delivery]. According to the DBIA, the design–build approach offers advantages to owners, including: "One team, one contract, one unified flow of work from initial concept through completion." Debate on the merits of design–build vs. design–bid–build The rise of design–build project delivery has threatened the traditional hierarchies and silos of the design and construction industry. As a result, a debate has emerged over the value of design–build as a method of project delivery. Critics of the design–build approach claim that design–build limits the clients' involvement in the design and allege that contractors often make design decisions outside their area of expertise. They also suggest that a designer—rather than a construction professional—is a better advocate for the client or project owner and/or that by representing different perspectives and remaining in their separate spheres, designers and builders ultimately create better buildings. Proponents of design–build counter that design–build saves time and money for the owner, while providing the opportunity to achieve innovation in the delivered facility. They note that value is added because design-build brings value engineering into the design process at the onset of a project. Design–build allows the contractor, engineers and specialty trade contractors (subcontractors) to propose best-value solutions for various construction elements before the design is complete. Design–build brings all members of a project team together early in the process to identify and address issues of cost, schedule and constructability. Proponents suggest that as a result, design-build alleviates conflict between architects and contractors and reduces owner risk for design errors. They argue that once design is finalized and construction begins, the greatest opportunity to achieve cost savings has already been lost, and the potential for design errors is greater, leading to change orders that create cost growth and schedule delays. Proponents note that