I agree with Roberto, actually. I was entertaining the thought today, and in concept seems okay, but why would air pockets cause overheating issues unless it was a large amount? Also, I don't think that air pockets would cause coolant to burn off, and even if so, would it escape out the exhaust or the overflow resevoir? But, I do not really know much about the cooling system or cars in general, so I could be dead wrong. Regardless, ot won't hurt to bleed out my system. Probably will flush the system and then bleed on my next day off. Should probably replace my oil as well, just so I know what's in it. And while I'm at it, I'll flush the oil system as well. Probably won't solve my mystery, but it won't hurt, either. Plus I can get a closer look at the oil and coolant for examination. Still not entirely convinced this isn't a head gasket issue.
Wherever you go, there you are