Furthermore, since peer review is fallible, I don't believe Clausen's identical mistake making it through peer review proves the process any less important.
Perhaps Clausen's criticisms were not well intended, but wouldn't any respectable scientist demand rigor before seriously considering such a hypothesis? After all, the burden of proof is not on Clausen.
The valuable thing isn't individual peer-reviewed papers, it's bodies of peer-reviewed works.
"Peer-review" as most people think of it -- the vetting of papers by a few reviewers before publication -- is the start of the process, not the end. Peer-review is what happens after your paper is published and your peers -- the people who read the papers you publish -- read your paper and discuss your paper and try and succeed or fail to replicate your results. A journal isn't "peer-reviewed" because a couple of schmucks read the paper before publication; that's just the scientific equivalent of Fizz-Buzz to avoid wasting everyone's time with obvious crap. It's "peer-reviewed" because it is widely and critically read by a large number of practitioners in a field.
You should never regard an individual paper uncritically just because it is published. Later, in light of a larger body of research, you might regard a paper as particularly insightful or seminal.
To generalize a little more: science isn't about single pieces of data or single experiments. Science is about the process. Experiment/data -> idea -> experiment/data -> refined idea -> ... until the idea and the data match to the greatest possible degree (a temporary state of affairs, until science in other areas makes it possible to refine measurements even more tightly.)
A single paper, even one with solid methodology, extensive data, and clear patterns, is just one part of science. Replication, refinement, methodological improvements, identification of weaknesses, etc. are what make the whole institution of science so powerful.
http://www.researchgate.net/profile/Mike_Oaksford/publicatio...
http://www.pfeifer-research.de/pdf/pfeifer08rh.pdf
I can see how Clausen comes off as snotty. But his response is pretty neutral, even if he praises peer review as a filter beyond its actual merits. He sees a lack of appropriate effort to establish the claim from a nobody, why should he not be skeptical of such claims in general? It's the same heuristic people like Aaronson make on being highly skeptical of the latest P==NP or P!=NP proof uploaded to arxiv.
Had the data come from someone with a proven track record in the field, he may have found it worth his time to peer review it himself.
Appeal to authority is not always a fallacy. It would have been fallacious if he was outright denying or accepting a hypothesis as being the logical conclusion based on one's standing. All that I read from it, however, was that he had a hard time believing it, and would not spend the time to look into the data personally, but that it should be reviewed.
I don't think it's illogical to take more seriously the hypothesis of someone with a proven track record of good research.
Are you describing logic/science/debate as you believe it to be or as you believe it should be? If the latter, are you suggesting ending peer review?