English proficiency is entirely dependent upon context. In graduate school, i may as well have had a kindergarten proficiency when it came to having too many topics in a term paper. To have a booklet given to the entire class on writing a term paper correctly was a LIFE SAVER!
However, it seems insane and inane to take an english proficiency test and be asked - which answer is correct to the question: 'how are you?' i'm certainly not going to answer, 'i'm in the living room.'
Try reading the New Yorker magazine. If you can make heads or tails of it - you're probably proficient. If you can read Reader's Digest - you like to be poetic, like jokes, and you like the average stories of average middle-class people/americans. I'm sure there are other magazines like this in other countries. Sort of 'guide the lame and blind' -especially with LARGE print.
My ideal, however, is to have plenty of time and read a few lines from bob. His english proficiency is normal - but he has some creative ideas. And, he didn't steal them from anyone. I like to read things that are entirely the writer's own ideas and not plagarism. Plagarism is a sign of laziness and is worse than not being proficient in English. (however, i have done a little at the start - when gleaning information from books,etc and then attempt to write it in my own words).
The difficulty in writing always seems to come down to how best to present information in an organized way. If you have a disorganized mind - you don't always put the information in the right order - or present it with the right vocabulary. When this is the problem - you need a proof reader. Having one doesn't make you less proficient - but it can increase your proficiency.
OK blah blah blah (never write etc.) on a college scale? I'm probably 7 or 8. I do make mistakes when it comes to writing too much. Editing is my new theme. Three or four times. Sometimes I'll have premature cognitive comments or little things that are just not entirely correct in the context. Grammatical things, too.