I've read On Writing half a dozen times, cover to cover - including the whole thing in one sitting, the first time around.
I've been published.
Writing (and editing, to a greater or lesser extent, depending on circumstance and what's in the wind) is literally my bread and butter. And bread and butter's still pretty much all I can afford. Sometimes the butter not so much, actually...but bread's no problem and I did earn enough to pay an electricity bill once. That was a good day (not least 'cause it kept the lights on and the 'puter going).
I know for a certain fact that there are plenty of writers on here, some at a 'higher' level than others. I also know that a hell of a lot of them have read On Writing, and have read widely besides.
I don't consider myself a student of writing. I'm a writer. Studying writing might make you something - a literary critic, maybe - but not a writer. Reading for style is good, but ultimately your style is your own, and is generally something you more or less trip over. Someone once described my style as "Stephen King meets Roald Dahl". I can't hold a candle to either of those gentlemen, but I was nevertheless pleased by the comparison (it's very possible that I was being buttered up for some reason, but I'll take the flattery and run). Whatever your style is, you find it by writing your own ideas down in your own words. You may not recognize it for what it is, and it may (should, in fact) reflect something of your influences, but it'll be there, running through your work like a (hopefully rich) seam of coal in dirt.
While I don't consider myself a student, I'm always striving to improve. Perfection is, by nature, impossible to attain, but there's no harm in shooting for the moon.