Clearly teams are more than the sum of their WAR. The World Series champs evidence that. Last year, 76 wins and nowhere near the playoffs. They went out and got Tim Hudson and Mike Morse, two players who combined for 2.7 WAR in 2014. Meanwhile, Cain got hurt. Lincecum went from bad to worse - two draft products. As a team, the Giants WAR actually dropped by 1.4 in 2014, and yet, they won 12 more games and the World Series. This notion of incremental improvement is such an oversimplification. Nothing is static in baseball. Iinjuries happen, players get better, players get older, players get worse, players get smarter, players get concussed, coaches change, philosophies change, umpires change, etc. Way too many other variables to just tally the previous year's win total, add x-projected WAR of FA y, and say "the money for this guy won't move the needle. Not worth it." Rubbish. Get the best players you can, every year. Give yourself the best chance, every year. Then play the games and see what happens.