This is a great thread because it forces you to think about and consider your own habits, skills and limits. It's easy to be disdainful of the overloaded bagger dude on a known (and risky) tourist trap road, in a moment of whimsy or vanity, waving to a photographer at a very inopportune moment—just before initiating a turn. Easy to think, "Man, what a knucklehead." But if you haven't had a knucklehead moment from your own saddle, it's coming.
I won't and can't deconstruct his riding technique. But I do think the larger and more relevant lesson—mentioned by DirtDad—is that the more you can eliminate "factors," the safer and better off you'll be.
Riding is already inherently risky, with limited margins of error and serious repercussions for trespassing them. I mean, with your Tenere in your driveway, a moment of absentmindedness can lead to a 785 pound tip-over (do the fat-man math) that breaks your wrist or crushes your ankle. No photographer or even forward motion necessary.
So when and where and how you choose to ride factors mightily into the exposures you create for yourself. I personally don't like riding with others, unless we're going off road (which I'm gonna do this summer on the Utah BDR). I feel like with all the other factors to concentrate on and avoid, I don't want or need to be thinking about, watching, admiring, or worrying about another rider—even a friend—in front of or behind me, in particular with other vehicles around. That's just me, and my three R's: "riding risk reduction."
Probably an unpopular sentiment here, and among riders in general, but for me (and if like me, you love riding but want to mitigate risk), places like Mulholland and the Dragon and all the other thrilling, see-and-be-seen rider magnet scenes are probably best avoided. There's no shortage of glorious roads in much of this country.
As to habits, I also generally choose to ride as far away from traffic as possible, and even at times when it's easiest to avoid it. Early Sunday mornings in New England, far from the madding crowds, is a delightfully "fewer factors" time.
Don't mean to sound like a schoolmarm. I just think that beyond the particulars of the crash in the original post, and the other examples folks have posted here, it's worthwhile to consider "factor elimination" as a riding tactic to avoid your own elimination. And it doesn't have to diminish your riding joy one lick.
... that's a Triumph (Thunderbird), not a Harley. Just saying. 
