User blog comment:Godisme/Swords of Origin/@comment-1489595-20130116222008

Since I don't see any good rationale in turning Soul Societies two strongest fighters on each other with the expectation that only one will walk out this is a fake-out.

Whats really going on is that Unohana is training Kenpachi with an eye to making him stronger, with the acknowledged risk that it might kill one or the other. But the Gotei 13 is desperate enough to risk it to gain two awesome captain-class fighters out of it.

Otherwise the fight is utterly pointless if all you get out of it is one captain while sacrificing another. You end up with less then you started with.