I was tempted to see The Human Centipede, I really was. You know how much I love mad scientists, and people with secret operating rooms in their basements, and misanthropes who abduct people and do awful things to them, and all of that stuff. But it's funny: as soon as you make that mad scientist a German it's like putting a big sign on his head that says THIS GUY'S MENGELE AND WE'RE TALKING ABOUT THE HOLOCAUST NOW. And I have no objection to talking about the Holocaust, quite the opposite; but I object to using it to evoke sentiment in your novelty horror movie about sewing people together. Why go there? Is kidnapping people and sewing them together not horrific enough? I guess not!
Wikipedia says that the father of Dieter Laser, the guy who plays the crypto-Mengele, "participated in the war," and that an an interview he spoke of growing up feeling "like a child whose father was in jail for murder." I don't think I'm being unreasonable in assuming that Laser's father was a Nazi, and I bet it was cathartic for him to Nazi it up himself after a lifetime of German guilt, but if you're going to talk about how personally meaningful the role of Dr. Heiter was for you I think the literal absolute least you can do is actually bring yourself to say "my father was a Nazi." That's the sort of thing you really can't coyly allude to.