A hermeneutical revisioning of Nichiren’s key teachings [SGI] or leaving Nichiren's key teachings unchanged [Nichiren's disciples and believers] are fundamental questions for those seeking the Way of the Buddha. By definition, "key teachings" can not be changed and still lead to Buddhahood and the Buddha's Land [if Nichiren's teachings do in fact lead to Buddhahood and the Buddha's land].
Think of the key ingredients for baking a perfect cake. Were one to substitute crisco lard for butter or artificial fruit flavor for real fruit, you might fool a child or unsophisticated adult but you could never fool a gourmet baker. Likewise, the faith and practice of Ikedaism, might fool an ignorant person into believing that it leads to Buddhahood and Kosen Rufu [the Buddha's Land] but a Bodhisattva of the Earth who practices the Lotus Sutra teachings of Nichiren could never be fooled. Those who develop a bad taste in their mouths practicing Ikedaism are Bodhisattvas of the Earth. They are not fooled by the SGI cake. Once they take up the faith and practice of Nichiren, they will know the taste of the perfect cake.