It works as expected for any sub-objects of a body. But when you right-click on the body this command appears too and when clicking on it the tip is nullified. No idea if this is on purpose or not but to me it doesn't make a lot of sense.
Looks like I didn't actually read @chrisb's statement enough carefully. I agree doesn't make much sense. It could eventually allow to nullify the shape of the body when used in further Part BOPs, but it actually just lead to errors. So pretty useless and hazardous as a feature.