This whole method is rubbish. I worked for a company who forced this method on us. The fluctuation was astronomical. Pair programming is only useful in specific cases (like getting a junior up to speed or solving super-complex problems) but in other cases it is a colossal waste of time and an extreme demotivator. Fixing bugs in pairs is the most boring thing that ever happened. Not writing down anything is a surefire way to forget what was the supposed solution for problem X or why did we put workaround Y in the code... A horrible, horrible method, I'd suggest steering clear of any company which adopts it.