Board Thread:General Discussion/@comment-25360536-20140920031731/@comment-11051098-20140928201419

You also have to consider that as the old Zangetsu had no Asauchi base, the old Tensa Zangetsu was not a "real" Bankai, strictly speaking. How real it was is difficult to say.

Nimaiya reforged Zangetsu with an Asauchi - Hollow Ichigo is the true Zangetsu, the real spirit, and he's still there, so in one way, it's still the same Zangetsu and should logically have the same amount of power.

On the other hand, Zangetsu is now completely free of Old Man Zangetsu's suppressing, and as we don't know how strong Ichigo's full power is now compared to post-Dangai Ichigo, it's hard to say whether he's now stronger or weaker than the was when he curbstomped Aizen.