Okay, I will watch his later episodes. I would only do this for you!
I don't have tremendous experience with boxers, but I have some, and I've worked with very large, strong dogs. This rescue I volunteer at ONLY uses harnesses, though they attach to the collar for safety, so imagine trying to control a 120 lb dog in a harness. It is definitely a different perspective to walk an animal that can pull you off your feet. However, I believe Cesar should tell people not to use prong collars, and I do not agree with his high collar method at all. He was actually pulling dogs off their feet, and these dogs were not even particularly aggressive.
With a gentle leader, you have full control, because if you control a dog's head, you control its body. You pull, the head MUST follow.
I'm watching Victoria on Tivo now!