I don't think that there was another player who caused such a disconnect between how we here at TCB viewed the player and how the Astros front office viewed/handled the player last season than Felipe Paulino.  I can remember pacing about on a hot summer's eve chain-smoking my way through the frustration of the knowledge that six-man rotation would eventually squeeze out Paulino, and not Russ Ortiz or Brian Moehler (sadly, it's moments like that make me miss smoking).  The comments at the time expressed the same level of confusion to why the Astros weren't allowing this very talented pitcher to take his lumps at the big league level.

Thankfully, for us, Mike Hampton's shoulder flamed out and Paulino was given another attempt at the big league level. Unfortunately, Paulino continued his less than consistent way during that stretch, providing both glimmers of hope and, well, glimmers of the opposite.

The story remains the same for this endeavor: Harry Pavlidus provided the pitch/fx data and I'll try to divine what it can or can't tell us about Felipe Paulino's potential in 2010.  Hopefully we can get a true sense of just how much we should vilify the Astros if Moehler get's the fifth starter nod and Paulino get's relegated to the bullpen.

The wise place to start is Paulino's stuff.  PF_X is the horizontal movement of a pitch, with a negative number implying that the ball was x inches in on a RHB from the center of the strike zone when it crossed the front of the plate.  PF_Z is the vertical movement of a pitch, with a negative number implying that the ball was x inches below the center of the strike zone when it crossed the front of the plate.

There are a few things to like, right off the bat.  Paulino's curve ball is of the 12-6 variety as there is hardly any actual horizontal break, and, relative to his fastball, the movement is still focused on a vertical change.  Aside from the amount of "hump" that is present on a curveball, relative to a fastball, being a 12-6 curve is the second most important indicator of a successful curve.  Of course, it's also his least utilized pitch, but we'll dig deeper on that subject in a moment.

Then there's his slider.  Appealing, again, to the anatomy of a pitch series, the key to a slider is in the horizontal component. Paulino's slider tighter than we'd hope for, but, its still a pitch that has the horizontal component that is necessary.

Finally, there's his change-up.  The first thing to admire is that there is a near 10MPH gap between his fastball and his change-up. In terms of a pitch to utilize for southpaw, it remains a fairly effective pitch in terms of horizontal movement, but the minute drop in vertical movement, relative to his fastball, leaves it very mash-able. The most important correlate of a change-up is release point (i.e. how well it's masked), but we don't have that data to analyze.

In terms of Paulino's stuff, these numbers suggest that his best pitches probably go something like:

1. Fastball
2. Curveball
3. Slider
4. Change-up

And so it seems that I ranked the pitches incorrectly, according to rv100e (if you are unfamiliar with Harry's metrics, click here for definitions).  How it actually goes is (I was way off):

1. Slider
2. Fastball
3. Change-up
4. Curveball

These charts, I think, reveal a little bit more about what might be felling Paulino.  Consider his rather extreme platoon split, and then splice that with our empirical knowledge of his off speed offerings (besides his slider).  Indeed, of he his truly dismal starts in 2009 (defined, by me, as a game score lower than 40), three of the five came against line-ups in which the starters were predominantly LHB or switch hitters.

Yes, it's true that I'm citing a very small sample size here, but I think it's a powerful enough insight, nonetheless. What I glean from this is that Paulino really took his lumps against LHB because he had to use pitches that clearly aren't good.  Sure, there are aspects of the pitches that indicate they could become solid pitches and give Paulino the ability to perform well enough against a line-up dominated by southpaws, but for the present, it doesn't appear that Paulino has it quite yet.

So what should be taken away from this? Well, I think the answer to the title of this post is: start him.  But I think there's more to the answer than that. Start him, but don't be afraid to utilize Brian Moehler against at team that can stack their line-up full of lefties.  The man had a reverse platoon split in 2009 and spot-starting is pretty much his only real utility, so it's a perfect combination.  For the sake of the 2010 season, there's no reason not to try and minimize Paulino's deficiencies while leaning on the few strengths that Moehler has to offer.

The final caveat I'll treat you to is that when we're considering the efficacy of Paulino's breaking stuff, let's also not forget that Paulino was coming of a 2008 season that saw him rehabbing a nerve injury.  Perhaps, then, there's reason to be optimistic that his off-speed stuff will improve has his proprioception does as well.  This is not the most likely scenario given that Paulino struggled down the stretch as much as he did in other parts of the season, but still something to churn over in the back of one's mind.