Typically it would cause damage the piston face or head and cause damage to the rings more so than the cylinder walls. It doesnt make sense because if the O2 sensor is reading lean enough to cause a cut
(not likely), it would be more likely to need a soft cut(ignition) as to not cause an even hotter or leaner enviroment. A fraction of a second is all it takes. Detonation isnt so much the issue in what I was trying to say. Its more that if you already had a lean enviroment the ECU wouldnt want to or shouldnt want to cut fuel atleast by typical design in most cars I have experiences with. I do realize that it would take a good number of fuel cuts to cause real damage and it would have to be repeated possibly many times to do more than burn some oil and cause scoring. If a fuel cut was repeated the same amount of times but cause by an already lean condition in cylinders, the likelyhood of real damage is much larger
My understanding of it and my basic knowledge of tuning but I think you already knew all of that..
Kyle