I don't share the concern. My response to Lawler was too long for him to include in its entirety, so I'll post it here.
I don't think we need to worry about Ben Bernanke becoming a "shadow chairman." The blog is not as unprecedented as it might seem. Alan Greenspan and Paul Volcker both remain active public figures who not only comment on the economy, but also advocate particular policies. Greenspan has published several books since he was chairman, and Volcker has a think tank, the Volcker Alliance. Neither of them has become a shadow chair. We want our top thinkers going into public service at the Fed and other government agencies. These top thinkers place a high value on having a public voice, and the blogosphere is increasingly the forum for that. If serving precludes them from later participating in the public forum, we will have trouble attracting the best people to these roles in the future.
I think it is good to have a former Fed chair participating in a forum like a blog, which is freely available to the public and fosters debate. It is also a good thing if this blog brings more attention to the Fed and how it pursues its mandate. Since Fed officials are not elected, the Fed needs to be accountable to the public in other ways, and accountability requires that people are aware of the Fed and really thinking about and challenging its actions. In my dissertation I show that this is not currently the case-- people don't understand the Fed enough to be able to hold it accountable. I argue that the Fed needs a strong new media strategy as part of their communication strategy. If former Fed officials make their opinions public, the public will likely put more pressure on current officials to respond and explain their own views and any differences of opinion. This increases accountability. The Fed also claims to place high value on transparency, which is a change from the central banking philosophy several decades ago, so they should be glad that people formerly at the Fed are trying to explain their thinking in a clear way that helps people understand.
As a blogger myself, I think it will be very fun to have Bernanke in the blogosphere and to follow him on Twitter. He will bring such an interesting perspective about which topics are really important to think more about. The topics that interest him enough to prompt him to blog will certainly be topics of great interest to the rest of us bloggers. It will be fun to think through and react to what he writes.Wishing you a very happy Easter!