The concepts the subtitle's spoke of related to the video displayed on-screen, and aligned with the timings of said video in a coherent way. The subtitles accented the visual information I was receiving, and vice-versa, in an accentual role.

I could not get English subtitles. Tried for a few minutes, unfortunately.

I enjoyed the content of the video using the subtitles as delivered. It made sense and was informative. I doubt there were any egregious issues given the relative similarity of the two languages.

You only need to be able to hear German to know if the subtitles are OK. :)

You can go wrong in two axes.

1. The interpertation 2. The execution

he means the second way, he didn't notice any english grammar mistakes or unnaturalness.

It's like how good translators make Donald Trump sound smarter.

So if someone says "I do know German and the translations were all wrong", parent should feel free to say "Actually, I just meant the English grammar of the subtitles, not the accuracy of the subtitles itself" and you'd be just fine with that?

He's just saying that it's a fine video with these subtitles, so thr subtitles were fine.

The accuracy of the translation isn't that important. Who knows, maybe it was a bad video initially that got improved by "wrong" subtitles :-)