Bleach 60

[Assertn]

If Aizen was plotting all this time to bring out hollow-kaien, then that means he would've planned on some reincarnation of kaien to come to soul society in the first place (which i guess ichigo could be, since they mentioned the resemblance). I dunno, sounds infinitely impossible for anyone to plan for the sequence of events that lead a young boy bearing the characteristics of an ex-leutenant that also awoken his death god powers while simultaneously turning into a hollow who entered into the mix to begin with from an interaction with a death god whom lent him her powers.

Even the people who helped train ichigo didn't realize the hollow side until yoruichi saw that mask after the kenpachi fight.

[DarthEnderX]

I think people are giving Aizen too much credit. I think he's just been biding his time until one of the Death God's commits an executionable offense to enact his plan.

I don't think he really has any idea how powerful Ichigo is. Which is why whatever his plan is is going to fail.

Otherwise, he's fulfilling some rediculously convoluted 20 year plan thats going to work and bad guy wins series over.