I cannot speak for him, but to my mind, he's getting at the difference between being able to come up with an idea, and being able to explain it. If you've got a great idea, but you can't explain it so that others can understand it, it's unlikely to be used. Being able to explain yourself is a more useful skill, in more contexts, than any in depth knowledge of a particular problem space.

And that's before we get into navigating the political situation of getting ideas listened to. Knowing who to explain ideas to, and understanding how to learn their motivations are both important skills to navigating a social space like any company and team. And they are skills not usually taught during typical education in my experience.

In short, an idea is only as useful as the people who you can explain it to.