Maybe I'll do it if I ever get my replacement motor back. I don't like the way a cut spinner looks, but if it makes a big difference it's worth it I guess. I'll try with and without a spinner first and see what happens; if there's a big difference I'll cut a spare spinner and give it a whirl.

Of course I don't know if I have an appropriate tool to measure motor temperature for an experiment (at least to report on, fingers could be enough indication for myself).