The original article about the 41 shades of blue says that Google decided to test the 41 shades because another team pushed a slightly different shade and it performed better.

So, it looks like the designer didn't know.

I'd contend that's because most designers don't optimize for performance, they optimize for aesthetic. When those two are in conflict which should win?

It sounds like Bowman thinks the latter, while Google thinks the former. As a stockholder I'm thankful that's the company's attitude.