Not only does removing tall canes result in a somewhat smaller plant,
it also thins it out, making it seem less cluttered to the observer
(most pruning, you know, is done to keep the homeowner calm). To
begin pruning this plant, you first stare into your shrub (most easily
done in the winter when the leaves are off). Follow several canes
from the topics down to the base. Your job is to locate a few of the
very worst crossing, rubbing, wrong way (meaning it starts on the outside
and heads back though the center and out the other side) canes and cut
them off at or near (eg. 3") the ground. Sometimes the selected
victim is so wrapped around other canes you must cut it in several places
and take it out in pieces. You pull the the canes down slowly
using the weight of your body to tug them out. Or sometimes you can
toss them up and out of a very overgrown shrub. Mind your eyes!
Safety glasses are a good idea. I know many gardeners who have
suffered significant eye injuries.