I get dejected anytime I see mention that 3 years of anything is needed. Time frames like that, or larger, are appropriate for looking back - gauging someone's HoF credentials and the like. But for forecasting, which for me is 90% of the interest in coming up with numbers, I need something that is a little more nimble than waiting 3 years to see how a guy's major league career is already panning out. Not to mention, as jimmer states, it's too difficult to hold talent level constant for 3 years, whether of an individual player himself or of some aggregate like a whole team. Or, to extend Chief's automotive analogy a little, if I want to look forward to the 0-60 times for an array of cars, I probably will learn something from their respective 0-10 times, even if I acknowledge it suffers from Small Sample Size and will have to wait for the more reliable numbers. And I'll probably be able to rule out that it's a Maserati if it's really a Pinto.