User blog comment:Xilinoc/Ch. 591 - Marching Out the ZOMBIES 2/@comment-1268838-20140730193221/@comment-24099400-20140730204742

On the contrary, I think a lot of people are forgetting that Toshiro is still the youngest captain, a kid in comparison. As you mentioned even Byakuya had room to refine his bankai and the experience between them is immeasurable. Which means Toshiro is always still growing, he may be considered fodder by many, but he still isn't even at full potential. Despite this disadvantage he at least puts himself on or at least just below equal footing with much older opponents, although he isn't able to ultimately to kill many of them, he does incapacitates them (until they power up...with help). Back in the arrancar downfall arc Shinsui even stated to Starrk that with a 100 years or so he would even surpass him. That may not be relevant now (perhaps a far off future storyline if such a thing ever came to be) but it's proof Toshiro hasn't hit his developmental peak. If Rukia can do that much damage with her bankai after giving soul palace training despite not even owning the strongest ice type zanpaktou one can only imagine what a mature Hitsugaya bankai can do. It doesn't matter in the here and now, but it's still something I consider with his development.

I wouldn't mind that Plotkai Unohana theory, because I love her so much lol.