Short torpedo tutorial

[Pisces]

...Have the TDC operator enter this value and keep repeating (and adjusting) it so the TDC operator can keep entering the value. ...

What may be the cause of your perceived in-accurate AOB setting is due to the time delay between you (looking through the periscope) establishing the AOB visually, but following the target, and the TDC operator interpreting your command and setting the dial. After determining the visual AOB on that bearing you should not turn the periscopes/UZO until the TDC operator is done. Then you can turn to reacquire the target in view. And yes the AOB dial may show a different angle now, but that will be because the target is on a slightly different bearing as it is approaching or going away from your bow. (or aft if you are using tube 5)