For chuck roast, I'm curious about cooking it to a temperature that's well bellow what I typically would , like smoke it until it hits 135F, maybe cook it Sous Vide to 145F, for like all day long... In part to see if you could get it tender, and yet not be cooked to like 200F or more. To be honest, I'm also very curious about cooking a Brisket flat in similar way... I want to see if it tastes better , if cooked to lower temperature, but held there for a LONG period of time , to break down the tough fibers.... If that all goes well, sirloin would be something I'd want to try too.