"Things You Wouldn't Know If We Didn't Blog Intermittently."
I didn't know that word, eidetic, but from my general knowledge this is usually the case. He's just reading the "landscape" created by the numbers, just like we would enumerate objects around us.
A lot of people do awkward things when they're counting, I know when I do I always look away from where the numbers are and kind of linger off to the side before returning to it. It's an odd tick I guess of sorts.
Fascinating... though I'm not really qualified in any way to say this, I took a different thought away from watching him. Seemed to me that he was performing calculations and perhaps ”watching” numbers falk into place, then reciting them as he saw them.