Hey Pilot. I appreciate your analysis. You are 75% right. but not 100%. Bal word is basically used  in terai region and  that was not Bal actually "BAR" means hair of pubic area.When people came to KTM from terai, they want to be sober so they change taht bar to bal. If you have hair loss from your pubic area then you will care. I think no, so Bal bahyena bhaneko, Bhutla jharyo bhane ke ko peer.