Hi Flying freak
Please treat this as a light hearted conversation and thus bear with me. I am not arguing. Generally speaking, when I use the term "oil breakdown" like you did, I mean that the oil has stopped doing its job. High heat and many cycles causes the oil to react with oxygen and other things and turns it into something else, such as "not a lubricant". This is the environment found in automobile engines and industrial air compressors. In our R/C engines, the oil makes one cycle thru the engine and then goes out the muffler. Not much time to break down. Just a light hearted observation with no importance. I'm going flying.