I come from a background in nuclear engineering and "retired" to teaching about seven years ago. Having low performers in class does them a world of good. The curriculum is tough and can't be significantly watered down. I teach to the "smart" kids with the firm conviction that even the table scraps picked up by the lower-performing students are a better meal than what they're accustomed to.
While certainly "on paper", this might be true, I tend to believe that, more often than not, it depends a lot on the teacher him/herself. A good, motivated, and well-trained teacher can certainly accomplish what this physics teacher can do. However, I also think that someone who isn't that motivated might cause a backfire - the students, especially the "lower-performing ones", might learn to hate the subject after they're done with it.
My personal experience with students entering college and professed to hate physics has often been linked with them having a bad physics instruction in high school. So one can only hope that AP physics teachers are better trained, and probably are more motivated to teach the subject.