But that's the whole clamp, including a plate. Attach the LL strap to the clamp, not the plate, and use the clamp QR to attach/remove the camera from the strap, if you're comfortable with Manfrotto's clamp locking mechanism.
Jon, do you have personal experience with a Manfrotto failure? I've been using it for years and find it perfectly safe while lugging some very heavy and expensive gear over my shoulder. I wouldn't do that if I wasn't comfortable with the safety of the system.
Twice you brought it up. I believe you're an Arca Swiss fan but I see no reason to insinuate that the Manfrotto system is less than safe. It certainly has been in my experience. What gives on that?