Body hairs (when transplanted to the head) do develop in the direction of scalp hairs over time. The industry's conclusion is that they seem to reach about halfway there.
A few transplant doctors have been messing with body hair transplants for decades. It does work. But compared to transplanting scalp hairs, the results are very weak for the grafts/money invested. The hair cycles are different from scalp hairs and they stay dormant for much more of the time. 10 body hair follicles just do not cover the skin as well as 10 scalp follicles, even after the body hairs have had years to shift their pattern.
It's not uncommon for guys with transplants to end up wishing they had more after 20+ years because of the aging process. 'Donor thinning' is real and high Norwoods usually get the worst of it. Sometimes the actual transplants thin out a surprising amount over time. Or maybe you are getting several transplants to exhaust your donor supply but then one of the surgeries fails to grow. Etc. It's good to know you have SOMETHING left in the tank for a worst case scenario. IMO you should leave your body hairs in reserve for that.
If you are considering transplants, and you don't think your scalp hair supply alone can produce a decent result, then don't go down the transplant route.
