Fair enough. I don't see this "masking" as an issue, though. I'm curious too about signs of dyslexia in adulthood. I would bet that adult SVS dyslexics exist but are better adapted around the issue.
It is certainly possible that those adult dyslexics are better at handling their disorder. That would be a pretty strong point in support of the Sudbury Valley School. However that is not the point the school or you made. You both made a harder to believe claim that none of their students even had the disorder which strains credibility and makes me doubt the first point.
I've never claimed they didn't have dyslexia. I said they weren't diagnosed. And that they all have good SAT scores, without the need to diagnose and treat such learning disabilities.