Knowing your BATNA is important so you don't take a deal worse than your BATNA, but the whole point of negotiation is to get something better than your BATNA.
You should never lead a negotiation with your BATNA because then your counterpart is only going to give up the absolute minimum above your BATNA, thus depriving you of all the surplus.
You should never lead a negotiation with your BATNA because then your counterpart is only going to give up the absolute minimum above your BATNA, thus depriving you of all the surplus.