title: "Function calls are expensive" vs. "Keep functions small"
body: <p>On the one hand, I read or hear that "function calls are expensive" and that they impact efficiency (for example, <a href="http://www.youtube.com/watch?v=mHtdZgou0qU" rel="noreferrer">on Nicholas Zakas' Google tech talk</a>).</p>
  
  <p>On the other hand, however, it seems accepted that functions/methods are best kept short and should only really perform one task, as generally accepted in <a href="https://stackoverflow.com/questions/406760/whats-your-most-controversial-programming-opinion">here</a>.</p>
  
  <p>Am I missing something here, or don't these two pieces of advice run contrary to one another? Is there some rule-of-thumb that allows one to maintain a Zen-like balance? </p>