"Insofar as we can all agree when a measurement happened, physicists operating under Copenhagen are going to be just as effective as those who understand MWI."

"Insofar as we can all agree when a measurement happened, physicists operating under Copenhagen are going to be just as effective as those who understand MWI." Agreed. If you're only worrying about the mundane medium-sized world we live in and what QM predicts we'll see in it, MWI vs. Copenhagen won't matter. Here, it does, as he's apparently using Cop. as a part of his argument.