Wow. The slow mo was really good.
For all the talk about muzzle rise all the shooters, including Joe, seemed to have it under control pretty well. Of course it's a heavy gun, which helps, but how it's held must make a difference. I do believe that Carbine Williams had an effective way to handle it, but the Army wouldn't adopt his firing technique.
The one thing I missed was an explanation of how it worked, like you did on the Luger. There were lots of praises, but were there any negatives with the open bolt in the field? Also an explanation of the basic models. It was easy to see that some had bolt handles on top and some on the side. Why not explain the difference to the audience?