Any number of people are currently feeling some weird nostalgia for the days of Kyle Lohse. Jeff Gordon posited that we "need" Kyle Lohse and suggests that we should snap his 34-year-old self and his 3 year, $33m contract up off of waivers.
This bit of alternate history doesn't fly, unless you posit that the Cardinals would have replaced Jake Westbrook with Kyle Lohse. It also doesn't really make any sense to snap him up now,
Kyle Lohse has had a pretty Kyle Lohse year. Over 2011, 2012, and 2013, he has had xFIPs of 4.04, 3.96, and (most recently) 4.01. He is pretty much who we thought he was.
For a club with a patchwork of guys filling the 4th and 5th starter roles, it's awfully tempting to look at that and wish things had been different.
But there's very little reason to think things would have been better with Lohse.
First off, the rotation coming out of spring training was Wainwright, Garcia, Lynn, Westbrook, and Miller. In the alternate history where we signed Kyle Lohse, it's pretty obvious that the guy getting the short straw out of that rotation would have been Shelby Miller.
Shelby Miller has been much, much better than Kyle Lohse. Miller currently sports a 3.34 FIP which is better than any performance by Kyle Lohse EVER. Miller would have certainly stayed at Memphis until Jaime Garcia departed for the DL after 9 starts.
Had Kyle Lohse been signed, we would have missed out on 9 of Miller's first 24 starts. So for about 2/5 of the season so far, the world with Kyle Lohse would have clearly been worse.
Once Jaime went out with Swiss-cheese-labrum, he was replaced with Tyler Lyons and, later, Joe Kelly. Those three account for about 24 starts. There's been enough shifting around that it's hard to say exactly who was in what spot, but that seems to be about right.
The other patchwork pitching slot has been Jake Westbrook's slot. Westbrook pitched for a good ERA but terrible peripherals until he went out with an elbow injury. He was then replaced with John Gast, briefly. I'm going to lump Michael Wacha in here as a Westbrook replacement, even though it is hard to identify exactly where the 4th and 5th starter spots begin and end. Westbrook later returned from the DL with terrible peripherals and a terrible ERA. Those three also have 24 starts between them.
The Garcia/Lyons/Kelly slot accounts for 1.1 WAR among them and a 3.60 ERA.
The Westbrook/Gast/Wacha slot accounts for 0.2 WAR among them and a 3.98 ERA.
Kyle Lohse has been worth 1.2 WAR and has a 3.22 ERA. Other than an ERA blip, he's pretty much indistinguishable from the production we're getting from the Garcia/Lyons/Kelly slot.
Lohse would have been an improvement over the Westbrook/Gast/Wacha slot, but mostly just because Jake Westbrook in 2013 is awful. Of the 24 starts by this threesome, Westbrook made 17.
Basically, the only way Kyle Lohse would have improved our rotation is if he had replaced Jake Westbrook from the outset. Had we actually signed Kyle Lohse from the outset, we would have actually been worse off; the major difference is that we'd be getting 8 or 9 fewer starts from Shelby Miller, which would have made us worse. Kyle Lohse's 15-16 other starts would then have been taking playing time from other pitchers not named Jake Westbrook, who are mostly equivalently talented to Kyle Lohse.
Kyle Lohse's performance in 2013 is not some artifact of Miller Park. Adjusting performance for park by using FIP-, Kyle Lohse has a 110 FIP-. Two of the rookie pitchers are much better than Lohse, even adjusting for park. Shelby Miller has a 92 FIP-; Joe Kelly has a 102 FIP-.
The other replacement pitchers from Memphis have been more or less interchangeable with Lohse. Gast had a 110 FIP-; Wacha a 112 FIP-; and Lyons a 113.
Again, the one pitcher Kyle Lohse could be replacing is Jake Westbrook, who has a 131 FIP- on the season.
There's no reason to try to pick Lohse up off waivers. Jake Westbrook needs to stop pitching, but even if the club is willing to give him his release or put him on the DL, we won't be hurt by replacing Westbrook with Lyons, Wacha, or Martinez. For the rest of the season, Lohse is expected to be worth about 3 runs above replacement. Spending more than $25m to get what might be a one or two run advantage is preposterous. And even that modest savings only makes sense if the club is willing to get off the Westbrook train, which it has not yet done.
The current nostalgia for the Lohse era notwithstanding, the most significant problem with the 2013 rotation has been the complete collapse of Jake Westbrook. The club needs to fix that problem by getting him off the mound. Acquiring Kyle Lohse doesn't have anything to do with the Westbrook dilemma, either looking backward or looking forward.
If the Cardinals have $25m to burn, they have better ways to use it.