This is an excellent post I agree with wholeheartedly.
...and this is the part that particularly resonates for me:
Does the story have velocity? Do you change rhythm and tone? Reading out loud will unlock the music in your language. Are you using that music to its utmost, varying tempo, line length, chapter length? A symphony written with only gorgeous legato lines will grow dull and begin to grate on the ear, no matter how lovely those lines are. I think the same is true with language.
When I beta-read for others, or when I'm cleaning up passage of my own writing, whenever I get stuck on a line or a paragraph that just feels awkward, I start reading out loud. Well, under my breath. I find it's easier to pinpoint the spots that don't work when you can hear your voice stumbling and stretching.
Try it :) I swear you'll be hooked ;)