...yeah, I can now totally see the parallels to what selenak has been telling us about Fritz/Heinrich.

I don't think the "cunning plan" was actually a cunning plan, btw, in either case. I think in both cases the abusers had some warm-and-fuzzies, aka a love-hate relationship, and the acts of affection were genuine. And staring your own mortality in the face is something that warms a lot of people toward their family members, and Fritz and FW were no exceptions, imo.