title: How to estimate while pair programming
body: <p>Reading the <a href="https://rads.stackoverflow.com/amzn/click/com/0321278658" rel="nofollow noreferrer" rel="nofollow noreferrer">XP book</a>, I have a condtradiction in my mind that I cant address and am wondering if you guys can help.</p>
  
  <p>XP says write stories on index cards, assign those to a developer, have her estimate how long the task would take and then use pair programming to do the coding bit.</p>
  
  <p>So then her and the developer she pairs with must choose to implement either his or her task. Based on that choice the work they perform is then counted toward the estimate that she made for the task. Is that estimate still valid, because it seems to be dependent on who she is working with?</p>