He does, but he also talks about his own experiences as a writer with some serious addictions. Here's the amazon link for you to check out if you want.
http://www.amazon.com/On-Writing-Anniversary-Edition-Memoir/dp/1439156816/ref=sr_1_1?ie=UTF8&qid=1385860453&sr=8-1&keywords=stephen+king+on+writing

I enjoyed it, I'd recommend, but wouldn't say it changed the way I write. I just enjoy reading books about writing written by writers :)