"It seems that those most eager to postulate a designer would have trouble operating a can opener."
Well, I don't think I'd go that far. However, it would be an interesting exercise to supply a can and one of those wonderful G.I.-issue can openers to a mixed group of Freepers. Discovering who could figure out how to use one would be informative of something, although I'm not sure exactly what.
I Carried my Army can open opener for years, until it would no longer snap shut (kind of dangerous in the pocket that way). I used to horrify my wife by using it in the kitchen.