I had a long talk with a bike fitting dude who told me the same things about crank length. He said he now uses a shorter crank than his 1 foot shorter wife. They figure this out by doing the power...

Same here. I ride all 3 bikes, sometimes in the same day, so I want them to feel the same.

FWIW, I like my two mountain bikes and my road bike to be set up as close to each other as possible, including 180 mm cranks etc.