Pair programming, like many of the other XP practices, appears different in theory and practice. Pair programming as a voluntary activity should be encouraged, when appropriate.
It s important, however, to not lose sight of the fact that programmers need peace , quiet, and space in which to think and concentrate, despite Ron Jeffries claim to the contrary. The social aspects of pair programming can be very difficult. And, when you add it all up, you re still taking two programmers to produce what a single programmer would under normal circumstances.