Example that comes to mind: language learning. There's people in the language meetup circles that can discuss a language at length, etc and not even speak it w

Example that comes to mind: language learning. There's people in the language meetup circles that can discuss a language at length, etc and not even speak it well. They spent so much time learning factoids etc about it without actually immersing and gaining that "on the ground" ability. No amount of research is going to let you speak colloquial spanish in the countryside of Colombia, or wherever.