Sanity has no accepted definition. Views on what constitutes normal behaviour vary across space and time. A Tantrik who meditates on a corpse in a funeral ground may be regarded as a seeker by some and a deviant by others. People who claim to have the ability to leave the gross body at will and enter astral realms can't be easily catalogued into neat behavioural categories. One easy way to avoid confusion is to avoid all mention of what lies beyond the usually accepted norms in social interactions.However at times what lies beyond becomes manifest in the mundane sphere when the seeker is the least prepared.
An ardent devotee of Krishna has His blessed vision. What is it? Divine grace? Hallucination? Both? What parameters decide the label? Modern psychology is too narrow to encompass the infinite miracles inherent in human consciousness. Dwarfed deductions of pygmies cannot limit the majesty of giants. As Ramakrishna said, " Those who sell brinjals would do well not to judge the price of diamonds."