I think you mistaken what I meant. I definitely made it that it will take 2 attacks to disarm than one. I am aware of the battlemaster's ability, but one attack with damage, and one attack without is still one attack. I don't think a non battlemaster should only have to use one attack to disarm, unless of course they are disarming an untrained opponent.The DMG disarm requires you to give up one weapon attack. The Battle Master, on the other hand, can disarm while not only not giving up an attack, but while adding extra damage to said disarming attack.
So, no, the Battle Master isn't useless with DMG disarm in play. Far from it.
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