If you replace a shortstop batting 7th with 70 runs created (or whatever batting stat you favor) with a shortstop batting 7th with 90 runs created, those 20 runs are exactly the same amount of improvement as getting a 20-run improvement in the 3 spot, say from 120 to 140. The guy in the 3-spot will get lots of attention, have some visible game winning hits, and make everyone feel like they've got a big stud winning team. But those guys down the order are just as important in the overall.
Which is obvious, when you think of it. AVI stuff. Similarly, those guys lower in the order can kill you if they don't hit well. We think of a .700 OPS as unexciting and a .650 OPS as unexciting, and consider them equal. They aren't. That .650 costs you. Put a couple of guys like that late in the order, and you have a fan base wondering why the team isn't winning even though they have so many hitters in league leading categories.
All this talk about the Red Sox "core" being so solid seems to miss this simple fact. It's less fun to talk about Scutaro and Saltalamacchia, but their at-bats are just as valuable.
Second, the sports radio guys were positively giddy about the fun they're having penciling in lineups now that we have Carl Crawford. That "possible lineups!" create debates and conversations, and hence fun, is not a positive. It means that you have problems that don't have obvious solutions, but tradeoffs. Play the "possible lineup" game with the Red Sox and you will see what I mean. That you don't want Ellsbury and Crawford running over each other or occupying bases that the other could steal, and hence have to separate them, means you screw with everyone else.
Third, the advantage of going LRLR with batters doesn't matter in the slightest the first 2 or even three times through the order. It sometimes matters in late innings, eating up a bullpen, which can have advantages later in that series. It's nice, but not such a big deal.
Fourth, my views on stolen bases I have already told you. An extra base is of course nice. But a lost baserunner is bad, and giving away one of your three precious outs is bad, and the two together are terrible. You have to have better than 70% success for stolen base attempts to be valuable. So multiple CS times 3 and subtract it from SB, rounding down. Now divide that number by ten, and that's how many extra runs your stolen bases produce for your team. Not very impressive. Fun to watch, though. (And everyone should attempt a stolen base a few times a year, just to keep pitchers, first basemen, and catchers from taking advantage of you. Okay, maybe not David Ortiz.)
With all this in mind, let's look at the Carl Crawford acquisition. I like Crawford. I mentally add 2/3 of triples to HR (the actual number is 5/7, but that's too cumbersome) to compare power numbers, so his power isn't bad, it's just not exciting. His batting average is good, but his on-base percentage isn't exciting. He is a very good fielder for range - though that is less of an advantage in Fenway. He will make exciting plays, but apparently doesn't throw that well. He is very exciting to watch, perhaps the most exciting in the game. But it's not so exciting to total up his value at the end of the year.
This is a Boston team that had terrible injuries and underperforming pitchers that was still in it right up until the end, so the addition of Crawford might in fact make the Red Sox the best team in baseball. He improves the team as currently constituted.
But a little history shows that you could have had both Jason Bay and Victor Martinez for the same money. Not quite, but it's close. Bay got 4 years at $60M a year ago, Martinez just got 4 years at $50M. Add a year to each contract and it's still less than Crawford at 7 years. And I'm not sure you want Crawford at 35 and 36 so much. Bay and Martinez at 34 and 35 are certainly not significantly worse. And Bay is an equivalent or better player, generally. And, Martinez is a catcher who hits, which is hard to find. Bay was injured and had a terrible year last year, so if that's the trend it undermines my argument. There may also be some tricky sabermetric clue that says one or the other is on the verge of collapse. In that case, my reasoning doesn't hold. But absent that knowledge, I think Bay and Martinez would have been a better investment.
Given that we already let Bay and Martinez go elsewhere, I think Carl Crawford is a great pickup. I was very pleased to hear that news this morning. But we didn't have to be in this place.