So as not to gunk up Darrel's personal log with a bunch of training talk, I'll add my addendum here.
About the sandbags, I think it's a great training tool. Thrusting with an 80 pound sandbag is harder than using an 80 pound dumbbell. It's always moving around and such. But, it limits the amount of weight you can use since it's so unstable. I still use it though. I've got one workout where I squat clean the sandbag then go into a thruster. Then while holding it overhead, do a lunge with each leg. Lower it and then go into a burpee. That's one rep. I usually try to get about 25 reps. It's a kicker.
But working the rack position has been the most beneficial to what I deem buildnig strength in the upper body. I've noticed that my arms, from the elbows to the base of the neck, feel like they're now working as one unit. I feel like working with heavy weights in the rack position have really built up a lot of stabilizing and functional muscle in that area. Don't get me wrong, the first time I did a bunch of 135 pound squat cleans, my wrists and forearms were dead the next day, like tremendous pain turning a doorknob. My fingers kept slipping off the bar and I'd end up gripping the bar with one or two fingers. But it got better and my wrists and forearms aren't painfully sore after the last two workouts which involved 30 reps of 135 pounds thrusters and then 30 reps of 135 pound squat cleans on back to back days.
My traps hurt like hell though.
P.S. also second the shoulder dislocations. Best thing I've ever done for my shoulders.