There is a chemical in oats called "avenocasides" that may raise testosterone. Some blue swayers even take oat supplements. I doubt it does much to use oat flakes, but there are so many other fibers out there, why not use one of them instead?? You may as well avoid the oat stuff just in case, even if it doesn't do anything.

Eating protein and carbs together is fine. Worrying about mixing protein and carbs is for blue swayers, not pink swayers. The ONLY exception is for some people who must eat breakfast in the morning, it may be slightly better for them to have either pure protein or pure carbs. But that is at breakfast ONLY and not other meals. Protein and carbs at lunch, dinner, and a 3rd meal if you are having it is fine.