In my experience, the sharper the blade, the cleaner the cut, the less it hurts.
I had a knife I sharpened to an absolute razor-sharp edge, like mirror reflection sharp. It would glide across my skin so easily.
at one point it became a comforting ritual. Get home from school, pull out my sharpening kit, spend about an hour honing the blade, then slide it across my skin and watch the little rivulets of blood trail down my legs before cleaning up and waiting until the next time.