I think he probably chose his words fairly carefully: "feel so much faster". I don't think anyone argues that they can ship a piece of software noticeably fast

I think he probably chose his words fairly carefully: "feel so much faster". I don't think anyone argues that they can ship a piece of software noticeably faster using Vim or Emacs. Like you said, we're never limited by editing speed. But it's also true that you're not figuring out what code to write one character at a time. You spend most of your time looking at the code, figuring out what to do next. But once you've decided that, there is a little burst of activity during which the limiting factor actually is the motor skill of executing that desired action. In theory, all the little savings might add up, but again, I don't think anyone seriously argues that. I think it's much more that that microburst of activity felt less frustrating while they were doing it.