I have dealt in detail with the issue of Avatarhood in different talks and writings, you can check.
The important thing however is that the practice of yoga does not depend upon our belief or non-belief in the Avatarhood of Sri Aurobindo and the Mother. It rather depends upon aspiration, faith, sincerity, the ability to open and surrender to the Divine Mother and Her Grace.
As for knowing the true standing of the Mother and Sri Aurobindo, is can come only as a personal revelation and is not something to be debated and forced upon through a logical analysis. It is a thing of the inmost heart and not so much of the mind.
