@RealityCheque I'd say your assessment is about as close to my normal assessment as well. I'd assert though that it is unreliable to make the leap to intelligence based upon writing skill. In recruiting for a job, it is entirely appropriate and should be expected that you toss the CV's that have even a few simple mistakes on them. I, however, wouldn't do it because I thought the individual had below average intelligence, but because he/she did not care enough to put forth the best first impression possible. The writing skills demonstrated on a CV or resume' may not even be those of the prospective employee.

An internet forum on a game website, on the other hand, is an instance in which people are writing for recreation and perhaps doing it at times when they cannot put their full attention toward the task. My above post, about the changing nature of language vs. grammar, was an example of this. It is a first draft of an argument that I had a couple of minutes to prepare before jumping up to handle another more pressing task. If there are mistakes in it, it's probably due more to the fact that it's a rough draft and rough drafts are prone to having mistakes. It is not a reflection of my true writing skill and certainly not of my intelligence overall.