How would a WAR of 4 or so make Greinke worth it for the Giants. Would that be four years of playoff baseball and sellout seasons?
Win Above Replacement (Player) is strictly statistical analysis.
I believe the idea is that an average team will have a record of 81W - 81L. If that average team replaces an exactly average player with a player with a WAR of 4, the expected result would be a team record of 85W - 77L.
The average cost of one Win-Above-Replacement is calculated to be around $8 million for this next season.
It’s more complicated than that, but that’s the idea.
WAR is one of those stats that drives up salaries for above-average players.