Not OP, but there's a group of people who have essentially a good manager's understanding of a project. They understand the trade-offs, they can talk intelligently about technical choices and architecture, and to some degree can even talk about individual modules and classes and language choices.

But they blank at code and struggle with the basics. They get lost for hours at the most trivial bugs. It's weird, but it's very real. Real coding takes a certain kind of abstract thinking that some people just don't have.