Best lefty off all time? My vote is Koufax!

[AndrewJerome]

This is a fascinating subject. I really enjoy analyzing baseball history and player performance.

There seem to be a few disconnects in this debate.

One disconnect is how much weight to place on counting stats. Pro-Spahn posters in this thread rely on longevity and counting stats with what appears to be a decent peak, with a pretty good ERA+ across his peak years etc. Anti-Spahn posters believe he was a pretty average pitcher in regard to “stuff” since his K/9 doesn’t blow your hair back and wins are team dependent. He pitched a lot of innings and a lot of years, but innings eaters can’t get to GOAT status if they don’t provide elite innings. Essentially that Spahn’s peak is not enough to be the best lefty ever, even with all the counting stats. Koufax’s stats are obviously much different. One very good year, 5 off the charts years, some mediocre years, early retirement and nowhere near the overall counting stats of Spahn. Anti-Koufax posters essentially dismiss him outright because his lack of counting stats eliminate him from lefty GOAT status. He essentially didn’t pitch long enough to even be in the conversation. I tend to agree that the weaknesses of both Spahn and Koufax as described above eliminate them from lefty GOAT status. Both clearly were great pitchers though.

Another disconnect here is how to compare players by era. Snowman appears to be arguing that Grove’s pitching competition was weak and therefore his stats should be discounted a great deal. The ERA titles, ERA+ etc is tainted by weak pitching competition. Essentially that Grove was much better than his pitching peers, but since his pitching peers were very bad, him being much better than them should not be as impressive as the stats appear. I have always wondered about this, but I have no way of figuring out how to crunch the numbers to argue one way or the other. The 1920s / early 1930s batting averages went nuts. Hitters went crazy. How much of this was a result of bad pitching during those years? Anyway, Snowman, I am curious how stats can help us figure out which time periods were strong and which time periods are weak. It has always been something of a mystery to me. On a similar note, WAR is a bit misleading to me since it seems to value relative to replacement where replacement level is determined differently every year. The value of a replacement level player could be very different in a time period where quality of play overall is very high as compared to a time period where quality of play was lower. But how in the world can we figure out relative quality of play?