I need some experience reporting from the ones who have done pair programming, I noticed that lots of people recommend it but my experience was that at one point it's more efficient to sit alone, think and then write code than to talk with the other programmer (which can be very annoying to other programmers in the same office), do you agree to this? and if yes can you mention situations where pair programming is less efficient than traditional programming?

Actually, I'm more interested in Cons than in Pros, but if it's your own experience I would like to read both, the Cons and the Pros. I would like to read what you think about the Programmer who doesn't have the keyboard, what can he do in the meanwhile other than talking about the concept? or checking the code on the screen?