@ReiKai: What about the Sakenagi Longsword from Susanoo? Anything struck by that gets sealed into an eternal illusion.
That would be a no-limits fallacy, and unproven really. Never mind, really, as Kenpachi is much faster than Itachi anyway. Besides, if you include the anime, though the Bounto arc was pure fail, Maki Ichinose can create illusions with his zanpakutou and Kenpachi blew them away with just his aura.