Another angle of attack on this problem, which I hadn't thought of before, is mis-spellings -- Slinker has spelt "happening" as "happenning" twice, but Stinker gets it right every time...

Leaving alone the issue of whether it is really worth it to spend a lot of time on this mystery, testing services have dealt with some aspects of your problem. Especially the personality tests where they ask you the same question in many slightly different ways and perform some kind of analysis to determine whether you are trying to spoof the test by appearing to be someone you are not.

Your mention of a spelling discrepency brought to mind a scene from The Princess Bride where Westley was to add poison to one of the drinks, and his adversary was to choose, after Westley had shifted (or not) the position of the glasses. The bad guy goes through a series of qustions and answers trying to figure out Westley's thoughts -- "You placed the poisoned glass closer to me so I'd choose it. But I'm too smart for that, so it must be the one closest to you... But you knew I'd anticipate that move, so it must be the one closest to me after all." And so on for a few minutes or pretty funny dialogue. (I'm sure I got the details turned around, but you get the gist)

Is this guy deliberately mispelling a word or two just to throw you off? Does it really matter? It still boils down to a guess, doesn't it?

Even after centuries of linguistic analysis, and lately with some fairly sophisticated computer analysis, scholars are still arguing whether Marlowe wrote the works attributed to Shakespeare, or whether Shakespeare was, indeed, Shakespeare.

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"Computeri non cogitant, ergo non sunt"