Only if you're assuming all questions have binary answers.
For example in the traveling salesman problem you don't have to compute all answers to start converging on an average. A random sampling of solutions can start setting a bounds for average, and your grizzled salesmans guesses would fall somewhere on that plot. If they are statistically better than average then they are far more than good enough. Unless of course you think burning up the observable universe in finding the best solution is the only way to solve the problem of which trip uses the least gas?
Only if you're assuming all questions have binary answers.
For example in the traveling salesman problem you don't have to compute all answers to start converging on an average. A random sampling of solutions can start setting a bounds for average, and your grizzled salesmans guesses would fall somewhere on that plot. If they are statistically better than average then they are far more than good enough. Unless of course you think burning up the observable universe in finding the best solution is the only way to solve the problem of which trip uses the least gas?