Sorting the wheat from the chaff is Problem One you need to solve regardless of whether you offer below, at, or above market pay. I think the grandparent poster's point was that by offering well above market pay, you will have more of both (wheat and chaff) in your funnel so you'll be able to sort through more wheat. Assuming you have Problem One nailed you'll end up ahead of those offering below market (who might only attract chaff).