The second level comprises a subset of the apparent minority who don't fall for the damn things, who may dash off a curt reply consisting of a link to a Snopes article, or a tersely-worded explanation that exposes the gaping hole o' logic in the forwarded message.
The members of this insidious subset are those tempted by the apparent ease with which these ridiculous claims go viral: prizes for testing email tracking systems, dire warnings about carcinogenic NutraSweet, etc. And they want to write better ones, ones with such unprecedented plausibility that everyone on the planet will see it. As if the cumulative effect a billion people clicking that "forward" button, if such a phenomenon could even be tracked, would translate to an awed whisper from the universe of "Dude. That was SO COOL."
I know it's bad that I want to be part of this elite group. But really? It's because I'm not clever enough to pull it off, is pretty much what stops me from trying.