I could make a case for various skills in interpreting the books and paintings but the example is not the point. Being able to do-something-for-an-extended-period is too different from being-able-to-do-something or even know-something. Most skill challenges will be set in a time frame where Endurance won't become a factor.
Take Escape from Sembia as an exemple: Up til now we've heard of outrunning the guards, lose the guards in the crowd, create diversions, or slip through a secret passage. How can I use Endurance here? The whole affair will be over in minutes, what good is the capacity to run up and down the midfield for ninety minutes?