Buying catching means buying high right now. I don't think there's any way around that.
Varitek is an emergent disaster, and I say that speaking as someone whose inner child desperately wants him to retire with the Sox.
The 3-year-27-million-dollar question is whether there is another team out there who is willing to sign our very own Captain Defensive Intangibles at Boras rates, and if so, whether Varitek would snub the hometown discount for the respectful offer. I don't know, but my guess is yes and yes. Which will put the Red Sox to a decision, hopefully sooner than later if it happens. The magical escape pod of a hybrid player/coach position without roster ramifications does not seem to exist, as far as I can tell.
[topic="
http://sports.yahoo....lgns"]According to Edes (for example)[/topic], there are some bright spots on the catching horizon. But they are a long way off and the long, dark road of 672 OPS and falling looms between.
Catchers are the new yachts. Buying one that you're not going to regret in a few years is unlikely. But the Red Sox need a catcher, and everything hinges on Varitek. If they can get him to just a single guaranteed year (more opium, please), then I'll be drunk with ecstasy and will run naked into the street to flip over my neighbor's car. Two years would be difficult to swallow, but would frankly be a coup in this market. Even still, I'd be thinking that Buchholz for Saltalamacchia is probably close to a wash in terms of overall wins in the next two seasons, compared to keeping 'Tek on the short roster. But a lot of it also depends on the pitching market, and on what kinds of projections we use.
The thing with guys like Kottras is that you don't know. This sounds like a stupidly obvious observation when discussing prospects, but it becomes acutely relevant when the discussion is about whether to give up on a Clay Buchholz in the present reality. To use a poker analogy, sticking with Varitek and Kottras is drawing to a gutshot straight, while giving up a pitching prospect right now is drawing to four suited connectors. The Red Sox have a lot more ways to build a winning rotation through money and development than they have to plug the breath-bubbling chest wound at catcher. And the Red Sox as currently constructed are well-situated to capitalize on emergent young talent and great financial resources. There is no reason to go into a rebuilding/testing-our-luck phase. If you're going to mortgage the farm, this is as good a time as any to do it.
I apologize for contributing to the not-talking-about-the-Texas-catchers arc of this thread, and also for not offering much in the way of hard insights or conclusions, but some of the valuations here seem a little myopic. The question is not whether, say Saltalamcchia's performance above league average will exceed Buchholz's performance above league average, but whether catcher X's value above Varitek will exceed Pitcher Y's value above whoever ends up being the fifth starter in the real-world Red Sox of '09 and beyond. Replacability matters as much as intrinsic value when assessing these things. I'm not offering conclusions here, just trying to frame the debate.