Well, Whitey was always different from those Hollows in Vizards. OMZ mentions the time that Ichigo turned full Hollow (against Ulq), as one of the times that Whitey came to Ichigo's rescue. Plus at the end, he returned Ichigo to normal, even though, he could have recovered only his external injuries without closing the hole, thus remaining as the one in control, yet he didn't do it.
Originally Posted by paulbee
Also, what's interesting, Ishin mentions that acquiring the Hollow Mask as one of the points that Ichigo draw out techniques from his Zanpakutou by force (in the tunnel). Yeah, looks like Ichigo was seriously the only one that didn't know.