Your anecdote coincides with my experience working directly with a certain semi-famous programmer for the past 5 years. He's very charismatic and a great speak

Your anecdote coincides with my experience working directly with a certain semi-famous programmer for the past 5 years. He's very charismatic and a great speaker, and he has a successful business selling his experienced expertise and advice. But having pair-programmed with him many many times during that time, I was surprised by his inability to discuss real-world coding problems and their potential solutions beyond more than a superficial level. What I took from that experience is just what you said: there seems to be an inverse correlation. I could produce code that solved complex problems thoroughly and bug-free, and he could talk about them in an abstract way, but neither of us could do the other part.