Well since I'm dealing with this at the moment I'll drop my story on here. I'm coming up on 19,000 miles on my 13 DS so I ordered a new belt since some guys were having trouble getting them quickly so I could change it before any issues started. Belt came in about a week to GA and I called to set up a belt change service (drop off Thur pick up Sat). They were backed up so it would be later the next week, motorcycles don't run on Sun or Mon of course.
So I get a call and the guy says the mech looked at the two belts and the old one showed almost no wear at all. He then warned me its a three hour job and will run over $300 on top of the $100 for the belt. I asked him to look at a few small things on the bike but I'd wait on the belt swap.
Just for data gathering I avoid the rain at all costs, ride in eco on back roads which makes life easier on the belt too. I have never touched the adjustment nuts. I have taken the rear wheel off a few times and put it back on myself with no alignment issues. I've never heard any rubbing or clicking noises and the only reason I went to have it changed was Zero's recommendation to change it at 18,000 miles.
I think the fly in the ointment may be the set screw on the swing arm nut, a tiny 2.5mm allen screw that the service guy was complaining about. Its really hard to get to
he said, still not a tree hour job in my opinion. A drilled bolt and castle nut with a pin may have been a better way to go but that's water under the bridge.