Databook is about base stats of characters.Itachi has 5 without sharingan just like Kurenai.
With sharingan Itachi is light years above her but since databook is about base stats they have both 5.
Same for Kisame's stats is without samehada, Kisame has by far more chakra, force and equal ninjutsu, total is no factor here.
Thats odd and the outcome of their battle begs to differ. Point taken though, manga facts > my opinion. I still stand firm on the point that Asuma and Kisame are NOT equal (This is, unless you have another one of those pages that states that they are).
A problem here that there always has to be a winner. Kurenai losing doesn't explicitly mean that there is a definitive gap between their comparative skill, just that she made a wrong move... and she did. It wasn't Itachi's "superior" genjutsu skills that prevailed either, rather she accidentally made eye contact with Itachi (which she should never had done coming from behind), and he used the Sharingan's unique power to reverse her genjutsu back onto her... which she broke, so their genjutsu battle ended in a draw since there was no winner of the exchange.
Regarding Asuma and Kisame, their stats may be similar but this isn't DBZ, there are other factors to consider; styles, jutsus, circumstances, etc. And technically, Asuma had the missed opportunity to slice Kisame's head off right here:
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Now while yes, Kisame has been displayed to be way more powerful than Asuma, jutsu wise, their physical abilities are shown to be close and Kisame's mistake could had cost him his life regardless of his superior jutsus. That's how a fight works.
While two people with the same score may not be completely equal, they are relatively close to one another. Why is that disagreed upon? With people ignoring databook stats, people are left to making up their own personalized stats which often greatly conflict with the views of others and leaves argument and disputes entirely vague.
As I said before, the stats only provide information on some aspects of a fight between two characters, other aspects include a repertoire of known jutsus, weaknesses and drawbacks, circumstances, etc.
