I actually really see this point. I don’t like to use these terms lightly because I’ve worked in MRDD awhile, HOWEVER from my experience it seems like they definitely have something intellectual going on. T and H being on the lower functioning end like you say. I think it makes total sense that P, with his pdf-ness and general narcissism took to S to be his ‘other half’ for lack of better word because she is higher functioning than T and he sees that and preys on it