Ok, this surgeon needs to stop taking about nutrition and leave that to the nutritionists (granted I know I'm not one, but I've done enough research into these things to know that what I'm talking about is true, plus I've talked to my Nutritionist about this stuff as well) Surgeons are great at surgery, but would you discuss the chemical make-up of the gasoline you are using in your car, with your mechanic? No, you'd want to talk to someone that specialized in fuels. Surgeons are Mechanics, Nutritionists are fuel specialists.
Sure you don't need *THE* most expensive protein, but not all proteins are created equal, and using store brand... you are more than likely not getting all the Amino Acids and BCAA's that you should (or could) be. Plus, store brand stuff tends to have lower quality, less refined proteins which can lead to tolerance issues.
Clearly to each their own, but paying a little more for a high quality protein *IS* going to be beneficial.
Hell, not even every protein metabolizes the same. This is why I'm taking Casein at night and Whey in the morning. Casein is a much slower uptake protein and helps with muscle recovery specifically overnight while you are sleeping. Whey is a faster update protein and is used during the day for muscle and energy support. Having the proper AA's and BCAA's is pretty important.