Nice thoughts but no. It's a ten speed crank and a ten speed chain. The phase marks(diamonds) are lined up I have checked that myself and also two different professional mechanics have looked at it. As for the rider experience I have 20+ years of 4-7 k per year, and the last eight years on this bike, never happened before this year, so technique is not an issue. Perhaps by applying FB's suggestion about easing off a little I can keep it from happening but the fact remains for 7 years and many thousands of years it never happened at all, so there should be a fix, perhaps a new crankset but I wish someone could explain to me what has happened to the current one