It's not often that I say this, so let me get it out of my system: I think Paul Nyman is right. In his latest article on The Hardball Times, he talks about the bow-arch-bow system that is crucial to developing velocity, discusses the role of tempo, glove side action, and many other things. Of course, he uses a terrible quote to try and prove that Chaos Theory is applicable to baseball:

Voros McCracken: "I would say that you know almost as much about what a guy's going to do in the big leagues from his Triple-A stats as you do from his major league stats."

Gary Huckaby [sic]: "I'll go further and say exactly as much."

Eddie Bane: "That doesn't surprise me, but I don't believe it. I won 15 games in Triple-A two years in a row. I won seven games total in the major leagues. The level of play is completely different. I led the league (Triple-A) in ERA both years. I wasn't good enough to pitch in the major leagues."
In addition to misspelling Huckabay's name wrong in the quoted section, he also misspells Voros McCracken's name earlier in the article as "Varos."

At any rate, the above rejoinder by Eddie Bane seems like a blow to sabermetricians everywhere, but in reality, he's using dumb scout logic to prove a point. First of all, win-loss records are meaningless, especially in the minor leagues. If you look at Eddie's major league stats, he walked more batters than he struck out.

Secondly, Huckabay and McCracken could have taken a look at his minor league stats and ascertained that he wouldn't do well in the major leagues despite his low ERA. He simply does not have the stuff to get it done in the MLB. Eddie thinks that Huckabay/McCracken are saying that if you succeed in the minors you will succeed in the majors. He is wrong. It's how you succeed in the minors that will dictate whether or not you will succeed in the majors.

Paul Nyman shows his ignorance of how to properly evaluate a player's abilities via performance analysis by using this quote. However, the rest of his article is very interesting and I largely agree with most of it, with the glaring exception of the Inverted W being an acceptable arm action. Yes, putting your arm in a position of unnatural hyperabduction and causing your forearm to lay back in external rotation especially hard can result in high velocities, but there exists a great body of evidence that shows these mechanics are injurious. He then goes to show John Smoltz's arm action, who, as you may know, just landed on the DL with inflamed biceps muscles and an inflamed rotator cuff.

The second article is about Ben Sheets. David Gassko does a great job (as usual) breaking down the performance analysis side of Sheets, but Dan Loeterman breaks down his mechanics with a few things that are wrong. First, he shows this picture of Sheets compared to Beckett and says Beckett is in a better position to throw the ball since he is more "closed off."

Dan says that Sheets will rely more on his arm strength to throw the ball because his front shoulder is opened up prematurely. He's wrong. Look at Beckett at footstrike - his arm has barely passed through the horizontal plane! This will increase the violence of his arm laying back in external rotation, which increases the strain on his rotator cuff and UCL. Furthermore, what you really need to look at is the back shoulder - both Sheets and Beckett have them in the same place! This means that Sheets is also "closed off."

Now, I do not think Sheets has ideal mechanics. Dan says this about Sheets:

Despite the high leg kick, Sheets’ lower body is not especially active (discussed below), though he compensates by bringing the ball in a wide circle—the wider the circle going into release point, the more power—and slingshotting it toward home plate. He pushes off well with his back leg and has a strong follow-through with that back leg, indicating a good transfer of power from the lower body to the arm. (emphasis mine)

The bolded part means that Sheets takes the ball laterally behind his body in reverse rotation, which causes extra stress on the pectoralis major and labrum. This is not a good thing. It's also not "slingshotting" the ball towards home plate. The loaded slingshot position is something that Dr. Marshall teaches his students, which avoids unnecessary violence in the external rotation phase.

However, there is a silver lining here - a pitching mechanics analyst by the name of Chris Neault said this about Ben Sheets:

Sheets places a lot of horizontal abduction on his shoulder when he brings the ball behind him at the beginning of his throwing sequence—prior to the cocking phase. He brings his pitching arm far behind his trunk, and basically points his elbow and forearm beyond second base (to the right side of the infield). This is the beginning of the "wide circle" that Dan was talking about. This motion places stress on the anterior shoulder structures such as the anterior joint capsule, coracohumeral ligament, pectoralis major, biceps, and labrum.

Alright! Someone who speaks medical jargon like myself! He's basically saying the same thing as me - that the wide circle is unnecessary and stresses his shoulder far too much.

However, Chris says this:

Why do these injuries continue to mount for Sheets? The culprit appears to be his high arm slot. Although it’s partly responsible for the large 12-6 curveball, it’s also responsible for taxing the rotator cuff to the max. As a rule of thumb, the higher the arm slot, the harder the rotator cuff and biceps must work to stabilize the head of the humerus. This places stress on the rotator cuff interval, which includes ligaments in the front of the shoulder that also add stability. (emphasis mine)

I disagree with Chris on this part. There is nothing inherently wrong with a high arm slot, especially when you use your trunk to lean and keep the elbow below the acromial line to achieve that high arm slot. It makes no logical sense that a high arm slot would be harder on the rotator cuff than a lower arm slot when you consider the arm in relation to the acromial line is exactly the same (assuming no position of hyperabduction, which Sheets does not have) in both cases. However, a low arm slot can produce extreme forearm flyout since it is impossible to take the ball in a straight line to the target. Forearm flyout occurs on almost every release of a pitch; it happens when the ball is taken in an arc to the target rather than a straight line. No pitchers take the ball in a perfectly straight line (or even inside vertical, as Dr. Marshall believes is possible) with the possible exception of Hideki Okajima:

Regardless, we can control forearm flyout by attempting to establish a straight driveline (ho ho, now you know the inspiration of my site's name) to the target. After all, the shortest distance between two points is a straight line. From a physics standpoint, accelerating an object along an arc and releasing it on a tangent line to a point is inefficient compared to a straight line vector. We want to be as efficient as possible!

Wow, this article ended up being a lot longer than I imagined. To recap:

• I agree (mostly) with Paul Nyman. This won't happen often.


• Dan Loeterman doesn't know much about pitching mechanics at all.


• David Gassko is still awesome.


• Chris Neault wrote some very interesting things, and I look forward to reading more of his work (hopefully his rebuttal to my comments regarding high arm slot).