Must be: my first biff was at the 2015 Polar Bear Rally, on the Saturday ADV B ride. You must be the guy two camp sites over who told me the whole painful story less than 24 hours before I re-enacted it myself. Then I did it again at another ADV campout (Sanjoh's) a few weeks later.
I agree about the S10's limitations: I've only been on deep sand once since then and it's just nerve-wracking. I'm not doing it unless I absolutely have to... and if I decide I have to, I'm getting a WR. I'm sure there's some super riders out there who can handle it, but I'm just not one of them, and I'm tired of screwing up my body and having to fix the bike.
Dallas?! When I leave this friggin' sandbar, it won't be for someplace just as hot, flat, and crowded.