Hard to imagine, so to say, about not feeling it but an exceptionally sharp blade is pretty painless.
The first time I used a bow-saw, I was walking along with it somewhat carelessly and it brushed against my hand.
A minute later, I was wondering where all the blood was coming from.
I had inadvertently cut a tendon and had never felt it (other than the “brush” against myself).
But if my, um, manhood was cut off I think would sense a tremendous disturbance in the force.