[dfan]

IM David Pruess has aphantasia and can play multiple simultaneous blindfold games.

Pretty much everyone at my level (2000 USCF) can play blindfold. I always assumed that I was completely unable to because of my aphantasia, but when I heard about Pruess's story, I decided to work on it, and I now can, although with difficulty and very slowly.

Basically I still keep around all the information about where all the pieces are; it's just not on a virtual board that I "look" at, it's stored more abstractly. I keep track of clusters of pieces and relations between them. The fact that I have an excellent sense of the board itself (I know how all the squares relate instinctively) helps. But I still have to stop all the time and confirm where all the pieces are (or, conversely, what's on every square).

[dfan]

As an addendum, when I calculate variations in chess or Go I sometimes close my eyes because my "board database access" can be easier to operate when everything is purely in my head, as opposed to performing mental diffs on the physical board in front of me, which requires me to keep track of both real and virtual pieces.