The frustrating thing about this type of talk is that early on, you get the point that there's a lot of confusing and counterintuitive rules about how C++ behaves, and you spend the rest of the talk waiting for the litany of point-proving gotchas to finish. I figured that at the end, there would be some insight as to a particular language feature or design principle that was behind all these gotchas, but the primary insight appears to just be "C++ is hard, D shouldn't be."