How is Kakuzu's Gian a B-rank ability?

[Kamui Sama]

It took two raikiris to negate it and it still somewhat burned Kakashi's hands. Granted the Raikiris did not seem concentrated like they usually are but it is still seems like a very strong ability with some serious killing potential. Kakuzu is very powerful..

Also why haven't we seen Kakashi do more double raikiris in combat? It would be awesome

 

[-6 Paths-]

Ranks are utterly meaningless at this point. Kisame flooded a desert with a B-rank technique.
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[Kamui Sama]

Ranks are utterly meaningless at this point. Kisame flooded a desert with a B-rank technique.
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lol that's true