The idea is more intuitive with movement, because movement is in any case something you Do, whereas seeing just happens. So rehearsing movement can be seen as an inner doing of the same thing. Rehearsing seeing is not so obvious.
Face recognition is a special case.
Hard to believe, but possibly even true. We'll discuss this in class. Not sure what you mean here. This fits philosophical pragmaticism only in a very nonspecific way. The evolution of the ability to detect and act on affordances of course makes sense, as any functional adaptation makes sense.