@HaxeyeMihawk:
Nnoitra logically was probably a lot weaker than Grimmjow because he was originally #8 and iirc, Aizen made him #5 due to his cunning (and he only beat a half dead Ichigo and Grimmjow), so Kenpachi beating him with his two hand crap wasn't "ZOMG!" albeit the two hand thing was a bit dumb.
Nothing about Nnoitras cunning being the reason for his rank was ever stated. And it's true that he was once 8th, but Nnoitora gt way stronger whil Nell was away; tanking a person formerly 3 ranks above hims' released attack while he was himself unreleased.
Also the thing about Nnoitora is that he, like Grimmjow, doesn't have any special haxx abilities. They're both flat out physical fighters, and based on that, 5th having more strenght/Durability/power tha 6 is the only logical reason for Nnoitora having the higher rank.
Hell, this chapter Yammy even says "I don't care if you beat grimmjow, nnoitora, ulqoriorra" in that order, which pretty much clearly indicated increasing strenght.
So: Kenpachi beat an opponent even stronger than the one Ichigo had fought evenly with moments before.
@Tokoru:
But this is the same Kenpachi who also was able to crush Tousen and his Bankai and was literally fighting Komamura's Bankai before Aizen pulled his stunt.
Not to mention by the time Kenpachi finally took his eyepatch in his Ichigo fight, he was almost out of power himself and was just letting it all out for one attack. As I see it now, Kenpachi wasn't fighting with everything he had when he fought Ichigo the first time (remember, the early part was merely Ichigo trying to figure out how to cut him) and didn't use everything like he did against Tousen. (or even more than that against Nnoitora, whom he had the eyepatch ripped off earlier than he did against Ichigo and was forced to resort to kendo)
Tousen is a whole other problem. I’ll go through this step by step, but it all comes down to Kenpachis eyepatch.
First off, he took it off against Ichigo because it was his only option; Ichigo was absolutely stomping him. Kenpachi could tank all the hits, but didn’t get any in on Ichigo.
Secondly, when he releases it, his power goes through the roof. Ichigo himself says that it’s rising like crazy. And regardless of how wounded he was before basic shonen powerup rule is that a powerup like that regains stamina (just look at Ichigo). And Kenpachi says he’ll use all of this power to kill Ichigo, so he wasn’t exactly holding back. And finally, the fact tht it was only one strike was because it was the final chapter of the fight.
Even with this huge powerboost, Ichigo with his ”fighting with zangetsu” powerup had EVEN MORE power.
So all that this means is that Ichigo, especially once he got Bankai, by all logic also should have been able to rush the same people Kenpachi crushed, I.E. Tousen…WITHOUT EVEN TAKING OFF HIS EYEPATCH. I jsut checked.
So Ichigo +zangetsu > Kenpachi without patch> Kenpachi with patch>Tousen
Another little tidbit that messes up Bleach’s power levels completely is, as you said:
the early part was merely Ichigo trying to figure out how to cut him
In order to cut another person, your power should be on the same level as theirs.
Ichigo with mask + bankai using getsuga tenshou schorches grimmjows skin.
By the above equation, Vaizard Ichigo>>>>>> unreleased Tousen.
Unreleased Tousen cuts off Grimmjows arm.
And now, in this very chapter, Buyakuya/friggin cuts off Yammys leg, When a current-poweredVaizard getsuga tenshou was just able to nick him.
And remembering how Ichigo going all out could'nt even nick unreleased Ulqurriora earlier, i don’t buy anything about him being weaker now.
So yeah, in short, logic in Bleach, especially in regards to power, just doesn’t work.