The good BP that is – Baseball Prospectus – the annual forecasting bible aptly blurbed on the back page: “If you’re a baseball fan and you don’t know what BP is, you’re working in a mine without one of those helmets with the light on it” (yes, I’m egotistically quoting my egotistical self).

It’s basically 573 pages of the sports almanac Biff Tannen finds in “Back To The Future II” so the material to mine is practically endless, and you will find it as useful on September 30th as you will today. But the aficionado often goes first to find the collapses that time, tide, and the theories of statistical reduction insist will afflict players you are counting on for your team, real-life or fantasy.

In short: BP does not like Josh Hamilton’s chances this year. In the list of the biggest falloffs in WARP (“Wins Above Replacement Player” – basically a measurement of how much
better or worse a player is than the absolute average Schmoe you could
stick out there at his position), it sees Hamilton dropping from 6.9 last year to 2.7 this. Mind you, this does not envision Hamilton winding up as a player-coach at Round Rock; 2.7 still makes him the fifth most all-around useful leftfielder in the majors. The computers still suggest he’ll drop from 32-100-.359/.410/.633 to 22-77-.294/.356/.509.

While similar plummets are predicted for Aubrey Huff, Adrian Beltre, Carl Crawford, and Jose Bautista (try 25 homers, because “if teams are smart, it could be May before he sees an inside fastball”), the most intriguing of them belongs to Austin Jackson of Detroit. As BP’s write-up notes, Jackson led all of baseball with a .393 BABIP (Batting Average On Balls In Play – in other words, what you hit when you actually hit it). Jackson struck out 170 times last year and had a mediocre on-base percentage of .344, and unless those numbers alter positively and profoundly, if his “BABIP” just drops back from Ted Williamsy to kinda great, they see his WARP collapsing from 3.6 to 0.2.

The BP formulae always tend to under-promise for pitchers. Dan Haren, Felix Hernandez, and CC Sabathia are the only guys forecast to win as many as 15 games this year, and that’s obviously an absurdly conservative prediction. Nevertheless it is chilling to see the computer spit out the following seasons for some of the game’s “name” twirlers:

Chris Carpenter: 9-5, 94 SO, 3.21 ERA
Phil Hughes: 8-6, 109 SO, 3.74 ERA
Zack Greinke: 11-7, 166 SO, 3.52 ERA
David Price: 12-8, 147 SO, 3.46 ERA
Tim Lincecum: 12-6, 190 SO, 2.74 ERA

It also doesn’t look so hot for some of the game’s closers, listed by predicted saves: Jose Valverde, 20; Carlos Marmol, 17; David Aardsma, 17; Brandon Lyon, 15; Brad Lidge, 15.

Last year’s biggest predicted collapse was Derek Jeter, and in fact the BP boys and girls turned out to have been optimistic. This year, the accompanying biography makes me look like Jeter’s most hopeful fan:

“Jeter pushed for a contract of four years and up, which suggests at least one of the following: (A) while Jeter may be the closest thing the modern Yankees have to Joe DiMaggio, he lacks DiMaggio’s sense of dignity; (B) never mind winning, it’s money that matters; (C) the emperor has no clothes but doesn’t know; (D) the emperor has no clothes but doesn’t care.”

Ouch.

Still, the PECOTA equations don’t see Jeter getting appreciably worse than last year (9-66-.281-.348-.377 compared to 2010’s 10-67-.270/.340/,370) but does see the once mighty warrior’s WARP sinking to 1.0. For contrast, Jeter’s great 2009 season had a WARP of 4.2, the top two shortstop numbers for 2011 belong to Hanley Ramirez at 4.8 and Tulowitzki at 4.7, and J.J. Hardy is a 1.9.

Having pilfered so much of their hard work, I feel it’s imperative to throw out some teasers to get you to buy this essential tome. Granted, at the BP website, the computers refine and refine these numbers even as the season progresses, but right now they somehow see Ryan Rohlinger absolutely tearing up the pea patch for the Giants this year, adore Javy Vazquez in Florida and Lance Berkman in St. Louis, and see potential breakout years for Sam LeCure, Brad Emaus, and Robinson Chirinos that even those players probably don’t.

And I’ll confess right now I had no idea who Robinson Chirinos was. Another reason to secure Baseball Prospectus 2011. However much you think you know about baseball, they know more than you do.