This is interesting because, to me, programing is a deeply visual activity. It feels like wandering around in a world of forms until I find the structures I need and actually writing out the code is mostly a formality.

I would describe my experience of it similarly, but wouldn't call it "visual thinking" in the sense meant in the article, where one uses actual imagery and visual-spatial reasoning. Indeed, I almost completely lack the ability to conjure mental imagery (aphantasia) and I've speculated it might be because a part of my visual cortex is given over to the pseudo-visual activity that seems to take place when I program.

I'm especially sure my sort of pseudo-visual thinking isn't what the article means by "visual thinking" because I also use it when working through "piles of abstract math", which I take to very kindly indeed.

Is your "wandering" of this sort of pseudo-visual nature, or do you see actual visual images that could be drawn? Very intriguing if the latter, and I'd be curious to know what they look like.