Ichigo always seems to let the hollow run free untill the enemy is defeatable by regular Ichigo. Unfortunately this makes the Hollow very plot device-ish. Now I don't mind Zangetsu being a plot device source of power, but having the Hollow magically get Ichigo out of trouble is just bad, hopefully yor right Sasuke, and Ichigo will learn to harness the Hollow as he learned to harness Zangetsu.