Oh, I don't think Holmes *has* Asperger's - although he has a lot of quirks that fit, there's too much else that doesn't. He *understands* people and how they work and how to work them much too well, I'd say. Besides, I think diagnosing a character kind of misses the point; it doesn't actually matter whether he does or doesn't have Asperger's or manic-depression or any of the disorders you could pin on him, what matters is that he's Holmes in all his bonkers glory. I like psychology, but as far as I can tell the only certainty in the whole subject is that you can find a diagnosis to fit absolutely anyone, if you want to. I've just always thought it's an interesting point about him, that he has this mental or emotional glitch; it's not that he doesn't *care* if he's leaving a trail of emotional havoc in his wake, he's just utterly oblivious to it until it's pointed out. Something like that.
And yes, I agree that Reichenbach is far more excusable than DYIN. I mean, really. He FORGOT poor Watson hiding behind the bed. FORGOT HIM. I hope Watson gave him a sound smacking, frankly.