Specifically Greg Maddux, as a coach

The reasons are plentiful and I could go on and on about how great of a pitcher he was and how he knows every hitter, how he's future Hall of Famer, or how he's the only one of our awesome three pitchers we haven't had to kick out the door.  However, I recently stumbled upon the Wikipedia article about Derek Lowe, which adds a little more reason to hire Maddux.  Apparently, not only are Lowe and Maddux friends, but Maddux may be able to help Derek Lowe significantly with his pitching performance.

Both times that the Dodgers acquired Greg Maddux midseason, Lowe performed visibly better afterwards. He indicated that Maddux helps him considerably, and Maddux was often seen sitting next to him in the dugout.

That quote is taken right from Wikipedia so you know its true.

Slowing the game down is one of future Hall of Famer Greg Maddux's trade secrets, and Lowe watchers recall he went 8-1 over the two months that Maddux was a Dodger and Lowe's dugout companion. 

And that quote is actually from a real baseball writer with the Dodgers' Official Site.  But what is actually interesting is what I found after I took a little visit to ESPN bestowed with this wonderful new knowledge.

Now because these aren't seasonal stats, I can't do a ridiculously in-depth analysis, but I can calculate some ERAs and WHIPs enough to prove a point.  But first some history, Lowe and Maddux have been teammates twice, both times with the Dodgers.  The first was in 2006 and the second was in 2008, so there is a pretty good sample size of 125.2 innings.

During the first stint as teammates, in which Maddux is aquired at the All Star Break, DLowe went 8-1 with a tidy 2.38 ERA and a 1.18 WHIP.  Not bad when you consider his career averages of 3.82 ERA and 1.29 WHIP.  Perhaps his WHIP is a little high, but DLowe always has groundballs that find holes.  His groundball to flyball percentages were also quite good at 2.49:1 or 72% groundball. 

The second stint also spells out some good news, the difference here is that Maddux doesn't join the team until August 19, so I had to adjust accordingly.  Lowe went 6-2.  His ERA was a tiny 0.88 and his WHIP was 0.81.  Remember to look back at those career numbers from before (most effective if you gasp while looking.)  The groundball to flyball ratio is a less impressive, but still good, 1.67:1 or 63% groundball, right in line with his career averages.  Someone pitching with those stats would surely be worth 15 million dollars a year, if they are maintainable.

Greg Maddux may bring more to the table than intangibles.  He may also be able to help us get the most out of our "ace" starting pitcher.  Perhaps, he can help the other guys just as much.  But at this point I am no longer analyzing and merely speculating.

There is also always an outside chance that I am wrong (highly unlikely) and Derek Lowe is just a very strong second half pitcher, he does have good second half numbers in all seasons except 2009 and 2007, so this could all be coincidence, although the jumps aren't quite as large as when Maddux is his teammate.  Either way, the pros of bringing in a guy like Maddux have to outweigh the cons.

Hopefully, this hasn't already been addressed, be nice.