Kerbal Space Program

If you are using SAS target tracking to align with a target craft, and have selected "control from here" using a docking port that is not aligned with the central axis of your craft, then the SAS targeting will not properly calculate the angle and will likely cause your craft to face in the wrong direction.

This is because SAS target tracking seems to calculate the angle towards the target using the root part of the craft as the starting point rather than using the controlling part as a starting point. If while in SAS target tracking mode you chose to "control here" from a docking port not aligned with the central axis of the craft then you craft will continually try to rotate around the target because it is trying to aim the root part of your vehicle into alignment with your target which is not in line with your control point. This makes it impossible to use SAS target tracking to dock using an off-axis docking port.

If the root part of the vehicle is reassigned to the desired off-axis docking port then the ship is able to dock properly using SAS target tracking, however this is not possible while in flight and cannot be used as a legitimate work around.

In the image below, in an unmodded game, you can see that an off-axis docking port is selected as a control point, and SAS target tracking is activated, but the craft is not aiming the docking port at the targeted craft. Instead, although the craft is being aimed in the same direction as the controlling docking port, it is the location of the probe core that is being used as the starting line for docking alignment because the probe core is the root part in this vessel. These craft continued to circle each other as the SAS tried to rotate the probe core in line with the targeted port instead of the controlling docking port.