Germans have explicit, delicate and mostly fine tuned humor. I admit, they are not readily willing to show or share their humor. That doesn't mean they don't have humor.

I could post plenty of evidence. The problem is, it would require full command of German language, incl. familiarity of any applicable regional traditions and/or dialect. So it's not an easy thing to grasp.
I have yet to see a translation into English that reflects any of the delicacy presented in German humor. In my opinion, it's not possible.

Even within Germany, people from different regions may not have a sense for the humor of people from regions other then their own.

Humor exists in Germany. Plentiful!

Now, the Borgwards were in fact, no nonsense hard metal cars. Name giving? Well, Goliath for a wagon may make sense considering their coupe was named Isabella?
I don't know.

Ps, I am glad you have enjoyable memories of your Grandfather. I wish I would have known my grandparents.

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