i think it only works when they are seeing the
same thing... like they can read the same
movements since they both can see them. i think
only the rinnegan or w.e can see anything anywhere
thats y madara was able to undo the technique cuz
kabato showed obito with the rinnegan on
I think this has to be part of Madara's plan.
Now that part of Zetsu is attached to Obito,
Madara's using the Zetsu's unique
abilities to show Obito the image of Rin. I
don't think they would share eyesight like
that because then it would probably work in
reverse as well.