Some of the arguments down below read like: I tried driving in gear-4 and I disliked it, so I changed back to gear-5. Funny. Another one: One company forced me to drive in gear-5...again that company was plain stupid (or atleast the management was, for forcing you, in general).
Pair programming is effective when you are coding up while you are building the solution on the go. Its one of those sessions where its not possible to think up everything in your head. Ever had such moments where you didn't know all pieces of the puzzle? You can always say I would think up everything and then discuss in a meeting the whole solution. What if you went ahead and thought up the solution in a pair rather than discussing after you have laid out everything and then realizing you have to change it because you made a wrong initial assumption.
You cannot think up everything in your head (as another comment was there). Many times you do not have all the pieces and sometimes even if you have, you need to consult.
Seriously people, you are not getting the concept of pairing at all. Or I am just nuts.