Hi Hans. Fred Brooks? I have to read about it (the name "The Mythical Man Month" sounds interesting) About team sizes I read the two pizza rule from Amazon that it has interesting insights. In fact, I got deep about it in one of my recent articles in which I have shown how teams can tangle and virtually grow beyond our control.
Indeed pair programming should be done carefully. I often use it to level up beginners quickly. Yet, there are some concepts that need more time and practice. But at least, and the end, both should know and understand the code and how to maintain it.
About mob programming, how would look like pair programming with one driver and several navigators? That is mob programming, all the team doing "pair programming" together. That is great, specially when a new kind of feature or part of the code is built, or you need several heads to evaluate and propose changes. I have seen that they are really fast, faster that it might seem, and, in some cases, there are several drivers (but mostly cleaning details).
If you want to see in action there is a video showing it:
