Freinds of mine have been in bands with GG, and I met him before he came up with his suicide on stage thing in 1988. GG's early music was pretty good, once you overlook the fact that lyrically speaking the FCC would never allow his early music to be played on prime time radio. In the late 70's, early 80's, he was a fairly confrontational performer but not much more so than any of the other punk bands at the time.
I know that he had a wife and a kid, and they got divorced in 1983, and that could have een the impetus for him to get more progressively involved with drugs until he became more or less what you saw in that video clip.
Did he have Asperger's? No. Most likely BPD, NPD, (As the wikipedia article mentioned) and perhaps bipolar depression as well. The people that were in bands with him said that he could be very down to earth and engaging at one moment, and then be trying to beat you senseless a moment later. --This is pretty much a classic symptom of BPD, as I understand it. Also the NPD with a dose of some pretty severe histrionics would characterise his stage show. The only video of GG playing a full set of music without doing anything really weird was the reception of his brother Merle's wedding that a freind of mine videotaped.
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