The actual problem is that some time ago it was decided that modifications of properties also mark the property list containing the property modified (and than the containing data node). Personally I am not a fan of this decision and this task is a good example why. However, even if everyone now would agree that it wasn't the best decision, it would be a huge pain in the back to find and fix all the code locations that rely on this mechanism. Hence, I will close this task as Won't fix, sorry. :/