Board Thread:Theories and Speculation/@comment-28252336-20160512015637/@comment-732150-20160512024141

Both with Sharingan and Rinnegan, the manga always stressed that you're at your most powerful if you have both eyes of the same "set", so I don't think Madara would be interested in mixing and matching. If he could have a set of Tenseigan without having to give up his Rinnegan, then I think he would do it. The most TSBs a character was shown to consistently have was 10, which was Madara. Also, TSBs are not associated with Rinnegan. Sasuke didn't get any, and Naruto got nine, through his Six Paths senjutsu. Obito got his through the same mean.