I do think there is an overlap and someone with OCD could be considered autistic--not sure how to draw the line...
My son seems to have a certain way of doing things, must repeat things in the same way: For example, I have to walk in front of him before we leave the house. My older son was like this to the degree that he would return pretending he forgot something if he wasn't the last one out.
I do think my younger son has more complex patterns some I'm aware of and some I'm not that interfere with experiencing things from a broader perspective. For instance, when we go to the library, or wherever we go, he always has questions to ask, something specific he's looking for and it's ALWAYS a challenge. He told me one time while walking out of th elibrary, that he liked the actual search for something. Funny. I think the search is almost a stim or a pattern that he's caught up in because he HAS to go right to the reference person or person with authority/knowledge with his questions. It begins with "I wanted to ask you a question..."
He loves the investigative stuff. So maybe this is OCD? The drive, desire to search for some particular?
OCD is prevalent, I think, because it's a way for people to make attempts to exert control when they are feeling pressure.
Maybe it's to a more extreme degree with people/kids on the spectrum?
equinn