In January 2015, Sam Miller of Baseball Prospectus assessed the farm systems rated No. 1 in the respective years 2004 (Milwaukee’s), 2005 (the Angels’) and 2006 (Arizona’s). His findings: “All three got substantial value out of their cores … But none of the three teams won a World Series or even made a World Series. The Brewers and Diamondbacks only made the postseason twice each.”
Then: “What a club with the best farm system in baseball can expect: Around 100 wins above replacement, most of it at sub-market prices, peaking three to seven years after the rankings come out, but some remnants of that value lasting into the next decade.