[TorpX]

I think the idea that track angles had to be 90 degrees, or nearly so, and gyro angles zero, or close to it, is something of an old wives tale.

Here is a pertinent quote from Roscoe's US Submarine Operations Of WWII. [I realize this is not the same as KM experience, but geometry is geometry.]

Throughout the war the percentage of hits was more or less constant for track angles between 60 and 120 and ranges between 1,000 and 3,000 yards. Within this region the scored hits averaged 36%.

The percentage of hits was independent of the gyro angle for values of the gyro angle between zero and 40.