Genetics and a bit of dice rolling. That's the biggest part of the equation it seems. I have only one specimen to work with (and I am not inclined to create more), but he was reading at 4 and currently at 6 reads at a 3rd or 4th grade level, despite still being stuck in kindergarden until September.

Sure, we read to him, and we make him read aloud to us too, but we're really just catalysts. He can make himself comfortable in a chair or on a sofa and read comics (Donald Duck, Asterix, etc.) for hours without any prompting (which, honestly, is a really nice feature to have on a child). I expect we'll be able to coerce him onto autonomously reading suitable books in addition to comics by next year too.

I do strongly believe that him seeing us read, and being surrounded by (actual paper) books helps. It means he grows up in an environment where books are normal, not just something you must grapple with because of school.

I don't like the heavy training implied by the article though. I want to raise a kid who likes reading, not one who will resent being pushed to read.