Soka Gakkai's unreliable criteria derives from the World of Anger (conceit and arrogance)

"Fully confident of my own judgment and ability, I have not the slightest doubt." -- SGI leader

We are confident of the judgement and ability of Shakyamuni Buddha and Nichiren Daishonin, especially when our own ideas, judgement, and ability conflict with theirs. Your criteria is an example of following the person rather than the Law. You learn arrogance and conceit by following an arrogant and conceited man. We learn humility following the Eternal Buddha and his messenger.