User blog comment:Xilinoc/Ch. 548 - The Thin Ice (hopefully fixed version)/@comment-1747976-20130912153845/@comment-5398287-20130914145127

Here's the thing: Ichigo has never consciously activated his Blut. Every time it has been used, Zangetsu has been the one using it, i.e. clotting Ichigo's blood during his fight with Kenpachi. So Ichigo doesn't need training, at least not with Zangetsu around, because Zangetsu is activating it for him.