[TorpX]

Originally Posted by banryu79

I suspect that was the case not because of trigonometry issue of the target solution, but for the specific problems with the impact pistol of the American torpedo.

You (and others) are confusing the gyro angle and the torpedo track angle. The TTa might be important with regards to the torpedo exploder reliability (or lack thereof), but the gyro angle would not.
No doubt the exploder issues lowered the overall percentages, though.

Take a glance at Aktungbby's diagram.

The gyro angle shown is, let's call it 40 degrees. The Torpedo Track angle is about 100 deg. You can easily have a large gyro and a near "perfect", 90 deg. TTa, or a zero gyro angle and a poor TTa.

In SH (3 or 4, it doesn't matter), people tend to favor 'canned' approaches because they think their hit probabilities are better, and because the game allows this. In real-life, unpredictable target zigs often forced skippers to use larger gyro angles, or pass up the opportunity.