I am a live bald guy. People train with me regularly.
If you are talking about blades, I went to a less than brilliant school of kenjutsu when i didnt know any better about the subject, and did some Iaido with a live blade shinken. Got my draw wrong and sliced my thumb down to the bone. Only found out later that most schools dont let you even use a blunted real sword for ages, and live blade somtimes for years. I should have been using a bokken, and when I look at the scar in my thiumb, and think about the feeling of the blade 'biting' into the bone, I wish I had been.
If you train with live weaponry, then you will always be 'holding back', and when dealing with real situations, that is how you will respond. Train with low risk weaponry, and you can train with full resistance, so be better equipped to deal with the real thing if unlucky enough to encounter it.
Just my thoughts.