Well.. i'd have to disagree, we use mobil in a couple of race cars. For it to burn in the ITR and nothing else, i'd find hard to believe. We would have noticed engine tempertures rising, or even on the engine management systems we have on the cars. Synthetic is a much more cleaner oil than regular crude/motor oil. The oil that im really impressed with is the Motul. We tear re-build motors all the time, and haven't yet found large portions of carbon build-up on the combustion chambers or exhaust manifolds.
-Jon