just thinking out loud here… i know that the nd-yag is for dark skin types , but i thought to myself that if the hardest part to remove hairs are on the shoulders and upper hands, then maybe the hairs are deep enough so the photons dont penetrate that deep in order to really effect the hairs … so why not use the nd-yag which has more penetration depth in those areas without any connection to the skin type…
i was wondering about the exact same thing 
Yags don’t work well on finer hair. If the hair there is fine, it’s not going to make much difference. If the hair is coarse, you can try it if you’re really sure it’s the issue of depth.