I just want to know how 9 tomoe sharingan vision field looks like, that's all.Yes rinne sharingan following ABC logic should be superior to the MS in terms of vison, but it is only an assumption that the leap in vision clarity is enough to be able to distinguish KB from the original. Just because her rinne sharingan vision wasn't shown, doesn't mean she can't see with said dojutsu. The juubi used the eye just fine to see
Well that could be because the byakugan has better vision than the rinne sharingan
That's the thing, you can't know whether she has tried or not and it proved ineffective at finding any difference.
Because that I assume she never used it to see.