If the auto trimming does not occur, does the Red Autopilot P/RST light not come on steady (disagreement between autopilot command and actual position). Thus an immediate go-around!
I remember taking the autopilot out at 60 ft on a practice autoland due to aircraft trying to snap left due intereference. The pressure required to land the aircraft in a safe attitude was surprising. Not something I would care to do in real Cat 3 wx.