I long ago unsubscribed from Jack Balkin’s “Balkinization” blog when it was taken over by people other than its namesake. If you look at its front page now, *none* of the posts there are Balkin’s. Balkin’s voice is the reason I wanted to read it to begin with. Granted, it has other fine people — Marty Lederman, as I recall, has some good things to say, as do Sandy Levinson and Brian Tamanaha — but they don’t have the voice that I signed on for.

Now Matt Yglesias’s blog looks to be in danger of going the same way. He got some guest bloggers when he was away in China, because either he or his employer believed that filling in space was more important than purity of voice. They may be right in the aggregate; maybe people don’t care so much about hearing Yglesias’s distilled voice, and instead care to hear about those *topics* that interest Yglesias.

I hope ThinkProgress has some way to answer this analytically, because my suspicion is that it’s dead wrong. I submit that the reason people come to Yglesias’s blog is for his particular brand of intelligent sarcasm deployed against his opponents on matters of policy. (The Yglesias-Glenn Greenwald feud — Greenwald, as is his wont, constantly inveighing at excessive length against centrists, whom he constantly refers to as “centrists”; Yglesias poking fun at Greenwald and lecturing him as he would an overintellectual eighth grader — is a fine instance of the species.) Merely reading another writer lecture on No Child Left Behind just doesn’t cut it.

Ezra Klein did the same thing when he was on the same junket to China, with somewhat more success. He got Mike Konczal, of the Rortybomb blog, to write about financial reform; Klein had been writing on the topic in the days preceding his departure, and Konzcal happens to be both better qualified and a better writer than anyone else writing on the subject today, so that was a good pick. He had some other guest bloggers during the China trip, none of whom I remember.

It’s one thing to use guest writers when you’re away. It’s quite another to let them contribute to your blog while you’re still in town. That seems to be what Yglesias has done today, allowing one Ryan McNeely to contribute while Yglesias is (presumably) elsewhere in D.C. chilling out. I’m sure McNeely is a fine man, but my first thought upon seeing his name under the Yglesias masthead was, “Who the hell is this guy?” I advanced to the next post in Google Reader posthaste.

My advice to Klein and Yglesias is similar to the advice for aspiring cafés I read years ago: be known *for coffee*; don’t dilute your brand by being known both for high-end coffee and mediocre sandwiches. My advice to Balkin and Yglesias and Klein is: we love reading *you*; we don’t love reading your proxies. We’re not going to run away if you fail to update your blog for a few days. So relax and keep your brand pure.