Romme, you're making things up. Bowman most definitely did not want "the first thing that comes to [his] mind" to be "taken as gospel". First, because design is a process, not a whim. Bowman is not the stereotype of a designer that you have in your head, he has a lot of experience and certainly knows how to work with other people.

The idea that you can just puke up a bunch of "designs" and then bucket test them to come up with the perfect solution is farcical. That's just not how design works. As useful as numbers are for validating and tweaking things, they can not replace the understanding of a talented designer. Furthermore, if you insist on being entirely numbers-driven, you will miss anything that is not being measured (such as the overall gestalt of a design).

None of this is to say that Google is making bad decisions or doing things wrong. Google is what it is. But I find it extremely annoying to get this armchair commentary, full of assumptions about how Doug did his work at Google that is almost certainly wrong, followed with a prescription about how design should work with engineering that is based on a complete lack of understanding of what design is.