Is it reasonable to expect the 02 mod to reduce my mayo build-up? I can't make my commute any longer, sadly, but I can run it one gear lower than usual to try and warm things up.I live in Texas so maybe not be best qualified to speak on English climate. I'm currently running LM Leichtlauf 5W40 which is reportedly formulated with additives to address piston ring clogging; and also reported to reduce consumption. Certainly the best oil I've found, and I would think fine for your climate. But yes, do everything else first and leave O2 pilot mod as last resort. Its changes to engines operating parameters are not insignificant.
Also, any experience with engine flush? The LM Proline is reputed to be good for smoothing things out. My engine is only 83,000, but I will be taking the valve cover off tomorrow to see the state of things.