^ as already Churchill said, the good ones are the submarines, the bad ones are the U-boats. "We" (Germany here) lost the war, so it is being told from a certain perspective..
But i like all documentaries, also looking forward to this one.
A bit of background as i see it:
The trial of KLt. Eck was a very bad example of justice. The court obviously needed a scapegoat, and the fairness of said trial is doubtful. It did not help that the accused and his defender were not properly prepared. The court could not provide evidence that Eck and the boat's doctor (also a combatant b.t.w.) had intentionally shot at survivors, but Eck and two crew members were shot.
Not one US captain was accused of shooting at shipwrecked, nor was any UK captain. While there is evidence some did.
For what i read and heard, german U-boat commanders and crews cared more for shipwrecked if the situation allowed, than their enemies. Not that allied crews did not also save german shipwrecked, but there seems to be a certain difference in proportion. And then the US submarine war in the pacific.
This is especially true for the german boats of WW1. The book "Die U-Boote des Kaisers" (~ "The Kaiser's U-boats") is a real good book about it, but i think it has not been translated into other languages.
Story about english trawler crews that met the same U-boat sinking their ship over and over again, and then again towing them towards the british coast. This was not an isolated case, but the british crews were not allowed to talk publicly about it, by threat of death penalty (traitors and all that).
The so-called "german unrestricted U-boat war" in WW1 was never really unrestricted, opposite to the british who conducted the war unrestricted and totally, from beginning to the end.