SciAm: "The Truth About Those 'Alien Alloys' In The NYT's UFO Story"

Honestly, I don't see how anything here should do anything to squelch whatever degree of freaked-outedness you might be experiencing about the story.
   Letzter's arguments basically only support the conclusion: Unidentifiable alloys would be extremely anomalous.
   Without other premises, this doesn't do anything to weaken whatever reasons we might have for thinking that somebody has some (currently) unidentifiable alloys. One man's Modus Ponens... and all that. I mean, if you already think that the Aliens hypothesis is very unlikely, then Letzter's arguments will give you reason to be more confident that there aren't any unidentifiable alloy samples in the alleged warehouses. Mostly the arguments just show: If there are unidentifiable samples, that significantly strengthens the Aliens hypothesis. (So either there are no such samples, or we have better reason to believe in aliens, or...) That is, Letzter's argument basically indicates that the explanation for the existence of unidentifiable alloy samples will likely be pretty weird. Which is not what he's really aiming for.
   That's sloppy...really ought to slow down and get all Bayesian up in here.

   Somebody here knows how to think about this better than I do, without a doubt.