How do you know that Design-bid-build is the most popular project delivery method?

Hi Ilan! I cannot speak for Jamie, but D-B-B is the most "traditional" method and has been around for many hundreds of years. D-B-B is likely still the most prevalent for public works due to the inherent bureaucratic molasses that impedes acceptance of alternative/integrated project delivery methods, but no doubt that trend is changing as it has in private works. Some studies actually show that D-B has overtaken D-B-B --- but it seems there may be some conflict out there. See for example:

 https://www.constructiondive.com/news/the-dotted-line-why-is-design-bid-build-still-the-no-1-process/517308/  

 https://www.dumpsters.com/blog/design-bid-build-vs-design-build  

https://www.momentumbuilds.com/design-build-most-popular/