If it's blatantly obvious that someone has AS and they say they "think" they "might" because of what they learned from their research, that's one thing. It's when someone shows no noticeable Autistic tendencies, yet declares that they absolutely are 100% Autistic beyond any shadow of a doubt yet won't cite the sources that made them feel that way that I have to draw the line.
I'm not saying that all those who are self-diagnosed are idiots, I just don't want to see AS go the same way as ADD did. I remember years ago when I was first diagnosed with ADD, it was fairly common, but not nearly to the extent it is today. Today there's so many people claiming to have it (to cover up laziness) that it's hard to take anyone seriously when they claim to have ADD or ADHD.
AS is already starting to reach the point where people just assume that anyone who claims to have it is just trying to hide their laziness or use it as an excuse for being an asshole. The thought of the one thing that makes the biggest impact on my life being ignored by the general public actually kind of scares me, my diagnosis has always been kind of my ace in the hole when someone (my boss or a cop for example) thinks I'm acting too weird to be sober.