the perfect enemy

the old axiom "never let the perfect become the enemy of the good" is quite wise, in and of itself. yet it all too often is used as an excuse for half-way measures.
it also begs more questions of calibration. such as 'if Perfect = 100% good, and 50% or 50.1% equals more good than bad, then can the axiom be restated as 'never let 90% become the enemy of 60%' ?

then where does it end? is 75% the enemy of 74% ?

the so-far reported intended makeup of Obama's government seems to indicate that he is well familiar with the old axiom, as it is so very far from "perfect" (unless of course one believes that there is no difference between Israel's interests and those of the United States)
it also seems that Obama is anticipating very hard times indeed, including another war. makes one wonder just what Gates told him?