I need Help!! Question about episode 293!!!

It's one of the more confusing aspects of the show, and part of the reason why I really think things have gone downhill ever since the start of this war. You're right, there's no reason for Ichigo to have not said anything. I've only really got 2 possible explanations:
1) He really really hates Momo.
2) Aizen executed the switch just as she was being stabbed, and he was so stunned by it that he didn't have time to react. (In this case, I'd question his effectiveness as a character at all. He's been through so much, and yet he reacts this slowly to an obvious problem?)
As for why the calmness, Ichigo seems to just like emotional buildup, that's all I can say on that one.
None of this made sense to me when I read them manga (had a long conversation with some friends on here about it actually), and it doesn't make sense to me now.

well i think he might have done the change whit hinamori the time he was going to be stabed by hitsugaya.cuz aizen has a really awsome speed and he said it was just his basic strenght so maybe he has an incredible speed.he could have done that chagen less than a secc and ichigo couldnt have seen that in such a short period of time.
meaning it was asien al along but at that very moment he switched places whit hinamori and ichigo couldnt react that quickly.after all aizen reached ichigos heart whit out him even knowing how it happened

i say that aizen just switched out super fast and by the time ichigo could totally realize what happened it was to late good bye momo u troubled child i will avenge you i swear! ban-kai!!!

The only explanation I can think of is that Ichigo was shouting the whole time after the switch was made. Not understanding why they didn't stop.

But of course the affected only heard what he wanted. Also someone mentioned that he must have made the switch before he got stabbed from his shadow. That also might not be true, he could have missed in reality, looking odd from ichigo's point of view. Maybe Then the switch was made, making it next to impossible for Ichigo to break them up.
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