I was curious about how accessible my blog is. By that standard, not very. 2/3 of the vocabulary in my front page of posts wasn't in the 2000 most common words, and 1/2 wasn't in the 3000 most common words. Yes, my Better Half teaches ESL.
I should try the experiment of forcing myself to use easier words and shorter sentences when covering science stories. I suspect I make too many assumptions. On the other hand, explaining what sigma is in each post makes them drag, and nobody is going to read a post in which they have to follow half a dozen vocabulary definition links. The post in which I tried to motivate symmetry arguments and multiverse speculation had so much background material that I'm not sure anybody but me stayed awake to the end.
My target is literate people who are going to know more than a measly 3000 words.
FWIW, AVI's word use ratios were about the same.