Just a side note bro, during the post work out period (pwo) you ideally want an empty stomach. Let me explain. When digestion occurs, blood travels to the stomach to form enzymes for digestion. Now PWO, you want as much of that blood in the muscles delivering nutrients rather than being diverted to the stomach potentially slowing down the 'nutrient superhighway'. That's why I like to use powder free form amino acid supplements and BCAA powders ONLY in the pre and pwo time. In the free form no digestion is needed as is the case with whey protein. Plus the free forms and bcaa enter circulation much quicker than any whey protein can boast. This keeps blood in the muscles and away from the stomach.
Now with that being said, would a whey shake pwo really slow your nutrient delivery down ? Probably not terribly, but if you're like the rest of us, you'll take any advantage you can get to gain more muscle in less time!