[nickelcitymario]

He doesn't say that crazy ideas by domain experts always work out. He makes two claims:

1) That if the crazy idea is from a domain expert, it deserves to be taken seriously. It doesn't deserve to be taken as gospel, but it shouldn't be dismissed outright.

2) He's betting (but not stating as fact) that if you did blindly support the crazy ideas of domain experts, you'd be right more often than you're wrong.

This is not the same thing as saying domain experts are always right. Simply that all things being equal, you're better off betting on their expertise over your own ignorance. But even better than that is to look into the matter until you have sufficient expertise to properly evaluate their idea.