Well, I didn't say autistics don't have a higher chance of having TS or NF than other people. I imagine there's a difference... though TS, and I'm guessing NF too, is so rare that you probably have to have a very large sample size for that difference to be statistically significant.
It's like, there are many things that can contribute to autism. Of those, TS is rare (I would guess NF too) enough that only a very small number of people with autism have it.
It's kinda like isolating a particular strain of flu. Most people infected with that strain of flu virus have the flu, but that doesn't mean most people with the flu have that particular strain of the virus.
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not aspie, not NT, somewhere in between
Aspie Quiz: 110 Aspie, 103 Neurotypical.
Used to be more autistic than I am now.