I mopped it every 30 min after 1,5 hour on the SF.I have done BBQ pulled beef a couple of times on my WSM and once on my SF using Chuck roast. It came out “ok”...taste was great, but even after slow cooking to 205F it was a bit chewy.
I hate to say it, but BBQ beef is really something that is best done in a pressure cooker or slow cooker where one can retain the moisture. Just my opinion, but perhaps I have never done it right. Always willing to learn.