Board Thread:General Discussion/@comment-24815992-20140531203303/@comment-5553481-20140606150310

Considering that Tatsuki was actually able to sense "something" from Aizen but not from Ichigo, could mean that Ichigo's reiatsu was simply off the radar... Theoretical example: Normal person is able to sense 0-100 power, Aizen was 105, he was able to sense 0-210, while Ichigo was 250.