of course it would. Lilly is under contract for two more years at 12M each Peavy is under contract for four more years at 8--15--16--17 with a 22/4 club option for 2013 trading Peavy for Lilly straight up, just as a thought experiment, would save us four million this year, while adding three million in fixed costs to next year's payroll. even with the pessimistic assumption that the time value of money is zero, the trade would be a salary wash. since Peavy is a better pitcher than Lilly, the trade would be a performance boost at no (financial) cost. obviously, though, we need to include the value of the prospects we'd lose in the deal as well. start by imagining a quantitative system that assigns dollar values to performance increments above league average (or, if you prefer, above replacement level). now, use that system to calculate the value of the prospects we'd be giving up: first, make predictions about the likely contributions of our prospects to the major league team in 2009 and 2010, the period in which we're directly comparing Peavy and Lilly...then, plug the expected contributions into your dollar evaluator. finally, plug Peavy and Lilly into your calculator in order to get a number for the Peavy-for-Lilly bump. I think you'll find that none of our prospects are likely to make 2009/2010 contributions that exceed the value of the 09-10 Peavy-Lilly bump. if you'll agree to that, then we already have a strong argument for doing the deal, especially since the Cubs are at the peak of the contention cycle and thus should place a strong premium on immediate results. but wait, there's more! given the magnitude of the contracts that baseball's best pitchers have been signing recently, there is plenty of reason to believe that Peavy's contract in the post-2010 time period will be a significant bargain. pitchers like Santana and Sabathia are looking at paydays in excess of 20M/year, and it is not hard to imagine that many major league executives will see Peavy as an equivalently talented pitcher. it is obvious that a Peavy-like talent on the 2009 free agent market would pull in far more than 16/17/22 in the first three years of a new deal, and while the economic downturn might raise questions about baseball's ability to sustain giant contracts, it is hard to imagine that marquee contracts will decline by 20 or 25 percent. so, if you agree to both parts --that the Peavy bump has more immediate value than our prospects, and that Peavy's contract is probably going to remain a bargain after 2010- you've got a great case for pulling the trigger even if Lilly must go as part of the deal...and, really, just one of those two arguments should be enough to convince you I don't know, I'm just worried about 2 things with peavy- how he would perform without getting half his games at Petco and most of his games vs the NL West, and also his injury concerns. I'd ultimately give up Lilly+ for him, but I just have a feeling that it would backfire.