Or, as Dr Malcom would say: life, uh, finds a way.
This should be a crucial piece of information about the tree laws, yet it's not mentioned in the Wikipedia article about the three laws [1], which is otherwise quite detailed. Reading this, everything makes me think that it was not a parody. I didn't feel like it was parody when reading the Robot series neither. He wanted an alternative to the Frankenstein plot where robots kill their creators and the three laws were part of the answer.
This I agree with. A big part of the fun of the series is that Asimov constantly plays with these laws.
Thanks for the clarification.
(I still completely disagree that "parody of rationalists who are so uncreative they expect a ruleset can actually impose control" was the intent. I believe not only the word "parody" is to throw away, but the whole sentence with it too. I understand better your stance now though)