"Y'all can all y'all really lose yourselves in a book."*I believe that's the most Southern** sentence I've ever said in my life. It's pretty funny sounding. It's also perfectly legitimate in Southern Vernacular,** the "all y'all" providing emphasis which the "Y'all can" by itself lacks. Y'all can all y'all... Y'all can all y'all... Y'all can all y'all...
* It's true. They're all ridiculously focused readers, to the eternal amazement of this rambly mind.
** Not "Southern-most" but "most Southern".
*** Some wayward souls may think that "perfectly legitimate in Southern Vernacular" and "funny sounding" are redundant, but t'ain't so. Y'all can all y'all borrow our vernacular anytime you choose. Try it on. We think you'll like it.