Well... despite what Tess is saying here, Kane's rank still makes a pretty big difference, since it determines much of the content you are seeing. Also, what I did't particularly like about the rank mechanics is that, if you (while playing Kane), are intuitively trying to be as good a sub as you can, you end up on the "K5sub route" (which has way too much unavoidable maledom for my taste). So, if you want to skip any maledom completely (as I do), you cannot rely on your intuition alone and need to resort to the walkthrough, Sancho's mod and/or savescumming.