There are SO MANY old, continually pollarded CMs around here. Once that is done, it can't go back to looking normal. Just have to keep doing it or get rid of it. We tried just letting the ones @ my mom's house go and they don't bloom well again if not re-pollarded. There's one in our yard that I think is as old as the house, 122 yrs. I don't mind the summer "lollipop" look but the bare winter "chopped sticks" is not something I would do from scratch on purpose.
