Originally Posted by minato uchiha
1. True, you are 100% correct. I wrote in the OP that this was pure speculation. However, there HAS to be a reason why Obito uses his Ms so frequently without suffering any side effects, and my thinking is that, Hashi's cells have something to do with it.
Kakashi has used his version of Kamui numerous times and hasn't shown any side effects associated with the MS (going blind) that isn't due to him not being Uchiha (the tiredness that follows use of his sharingan in either form). He has no involvement with anything related to Hashirama.