The times I've done pair programming, the co-pilot has been a lot more active than what you describe. While the driver types out the details of a couple of line

The times I've done pair programming, the co-pilot has been a lot more active than what you describe. While the driver types out the details of a couple of lines, the co-pilot will look at the surrounding code, figure out what to do next, and keep a stack of things to be done (while still keeping an eye on the code being written). Once the driver is done, the co-pilot suggest the next little task. This might lead to a little discussion, which is great, because you have two people who are really into the code. This has been pretty hard algorithmic work, though. No fleshing out hundreds of lines per hour.