For years teams thought walks were a weakness in hitters. We now know they were wrong (well, outside Cincy they know that). I am suggesting that if you think Greinke can be good for 4-6 years, as in, well above league average, that signing him last year was not necessarily a bad idea just because no one else has ever done it. If you don't think he'll be good that long, then I agree, the Twins should not have done it. For years, in football, teams punted on 4th down. Now, in HS and some colleges, where real innovation takes place, there are teams not punting at all in entire games. Lo and behold, they get more possessions that way, and win more games that way. over time, I do believe that people become smarter about how games are played, and that strategies and tactics evolve. When and which players to sign for how much, I think that can evolve over time, yes.