Given the current roster construction and ignoring salary, length of contract, etc., which player would you rather have in the Rays lineup:
Player A: 33-years-old, right-handed, last three years has averaged 145 games played and a .360 wOBA when weighed by plate appearances.
Player B: Turns 32 in April, switch-hitter, last three years has averaged 104 games played and weighted-by-plate appearance wOBA of .390.
The first question you (should) have is whether defensive value comes into play. In this scenario ti does not. The second should be "How many plate appearances does 145 and 104 games translate into?" Which I will provide in this space:
Player A three-year PA average: 573
Player B three-year PA average: 409
Now, which player creates more runs? The lesser performer with more consistent health or the wild card who offers more reward with his greater risk? Let's do some math.
Up first: Player A
We'll assume he posts a .360 wOBA through 573 plate appearances in a league with a .330 average. Let's figure out the amount of runs this produces.
.360-.330 = .030
.030/1.15 = .02609
.02609*573 = 14.9 runs
Okay, now Player B:
.390-.330 = .060
.060/1.15 = .05217
14.9 - 21.3 = -6.4
If you assume these players play just like this - which isn't a given, but none of us know any better at this point - then Player B needs only 286 plate appearances to equal Player A's output through 573 plate appearances. How good of a bet is Player B to reach that total? Well, since 2002 he's reached the 300 plate appearances threshold in every season but one, which just so happened to be 2007. Seven out of eight seasons is nearly 90%. Let's say you can trade Player A for Player B straight-up ... well, why would another team do that? Because Player B has a reputation for wearing folks down through his attitude. How many runs is that worth?
There's no set answer for that. Everyone will have varying degrees as to whether chemistry affects individual performance and by what extent. The poll taken last night shows that most people (as of this writing) surmised the effect of a bad attitude on team performance was worth five or fewer runs during a full season. Look at the math above. Even if five runs is correct - and really that seems like too much in my eyes - Milton Bradley still looks like a better option than Pat Burrell when examined in a world without contracts or money.