Re: Most overrated player in baseball?
If we're just talking about perceived value to actual value, I'm going with Mariano Rivera.
Now, don't get me wrong. He's one of the most effective pitchers of all time. His ERA places him 10th all time among guys with 1000+ IP, directly behind Christy Mathewson, Walter Johnson and Cy Young. Wow. That's some company. League adjust it and I'm sure it's even better.
But here's the rub: At the end of his career he'll have pitched a mere 1300 innings, or more than 500 fewer than Felix Hernandez will have at the end of the season and 1000 fewer than the notably short career of Sandy Koufax.
Don't get me wrong, 1300 innings of his level of dominance is quite valuable. But that cumulative value is something on the order of 40 WAR, comparable to Felix Hernandez. But would you call Felix Hernandez one of the greatest ever? Instead he gets thought of in the pantheon of modern greats like Clemens (140 WAR), Maddux (114 WAR), Johnson (110 WAR) and Martinez (89 WAR).
Of course, Felix has had just half a career, if that. If we want to compare guys to have similarly long careers in terms of years, we can compare him to the likes of Tim Wakefield, Danny Darwin, Kevin Tapani, and Derek Lowe, guys with long careers in which they ended up producing in the neighborhood of 40 WAR. And while you might be inclined to compare him Sandy Koufax
Ah, but you say that leverage, leverage is they key. Ok. So he pitched in more important innings. Firstly, why should he be given the credit for that? Are those innings materially harder? Not so much in my mind that it elevates a guy comparable a solid mid-rotation-at-best starter to hallowed status. But let's consider that. What's the arbiter of the value of leverage, saving games? His 90.1% conversion rate is stellar, 4th among the 103 pitchers with 100+ career saves since 1970. But should we really be that impressed? Eric Gagne and his 3.47 ERA is first. Dave Giusti and his 3.06 ERA is 2nd. Jose Valverde is 9th. Mike Williams, he of the 4.45 ERA is 15th.
The "r-squared", the coefficient of determination which tells us how strongly related to variables are, is a mere .07. Sounds to me like the save thing was mostly a function of being a "good" pitcher who pitched for a long, long time with a lot of nice leads to protect more than a function of his overall dominance.
Again, don't get me wrong. Mariano Rivera was the most dominant relief pitcher ever. But he was a reliever. And compared to starting pitchers and position players, individual relievers just don't do all that much to help teams win baseball games.
Games are won on run differential -- scoring more than your opponent. Runs are runs, scored or prevented they all count the same. Worry about scoring more and allowing fewer, not which positions contribute to which side of the equation or how "consistent" you are at your current level of performance.