because how well-spoken you are has an enormous impact on how smart you're considered to be

I'll back this up. I speak far more eloquently online than I do in real life, where my speech is highly hampered by a strong Cajun dialect/accent at times and a need to physically stop speaking to reach the ability to say a word my brain hitches on (like Jimmy from South Park).

So I'm often considered quite retarded, which leads to a lot of surprise to people who I can and do switch to a more serious topic and am able to list off large amounts of data and outpace most arguments. Not that I would call myself "smart" but my schooling at least has the physical documentation that says I was above the average to some irrelevant extent.