I count being horribly disappointed as being surprised, just with the sign reversed. That's the risk you have to take as a leader. But, yeah, if it's a high stakes, do or die situation, do what needs to be done, even if that's something like getting 3 different groups to work on the problem independently, or something.
Long term, if you have the right team, the positive surprises will more than cancel out the disappointments and the "meh" results. But, if it's a life or death type matter, fuck the long term -- you have to survive the short term before you start worrying about that. You can't manage or lead an organization that's at war the same way you would one that's at peace, and nor should you try.