Urban legend if you ask me. I "hear" that if you chop the whole plant, hang upside down until dry, then trim the buds, that the buds retain a better smell. My stuff always smells good, so I never tried that technique.
A local Native American I know removes the whole plant, root ball in tact, and boils the root ball with the plant attached. He boils for about 2 hrs then hangs the plant w/root ball still attached upside down, then trims when dry. I tried this and found no difference accept a lot more work.
Try one of your plants one way, then another plant a different way and see what works for you.
TMB-