Thank you for this wise comment Debashish. I like its "integral" perspective, somehow reconciling the either/or debate about the avatarhood of Sri Aurobindo (& perhaps that of the Mother also?). To me, attempting to resolve such a profound question from the limited viewpoints of normal human consciousness is fruitless.
Sort of like scientific materialists attempting to prove/disprove the existence of the soul by weighing a body at the moment of death. I'd prefer to simply acknowledge the possibility of more expanded levels of consciousness in which direct personal experience may render the question moot. For me, your recount of your conversation with Nirodbaran rings with the elegant simplicity of a deep truth:
...I remember asking Sri Aurobindo's attendant Nirodbaran, whether he thought Sri Aurobindo was an avatar. He said he had tried in many ways to get Sri Auroboindo to confirm this proposition, but in vain. But, he went on to say, this question did not concern him anymore. In fact, he felt it was a question that ought not to concern anyone. For him, Sri Aurobindo surpassed the acme of human possibility and perfection and gave a goal to his aspiration. In the growth to this goal, it may be given to him to know what an avatar is and that Sri Aurobindo is an avatar. At that point, the question of avatarhood would make sense, but not now. These words of Nirod-da have stayed with me since then and have moulded my approach to Sri Aurobindo.
~ ronjon Science, Culture and Integral Yoga