Saves and Leverage

When the Orioles signed Kevin Gregg, I suggested that installing him as closer wasn't that bad since it would allow Koji Uehara (the better pitcher) to be something of a fire-man. Can "non-closers" appear in enough high leverage situations to make such an arrangement effective though? I looked into the relationship between save opportunities and leverage index for 2010 relievers at Beyond the Box Score. Check it out.