I've done close to this in the past. There's nothing terribly wrong with it over the short term. The X-factor in food science is you still can't duplicate the nutritional values found in whole foods. Eventually this catches up with you and your gains will come up short. I've observed a loss of (muscle) fullness even over a period of a week or two. As someone said, add some Green Foods to your list. At least your stool will now be colorful.