What an amazing article. And what amazing analysis of this 30 years old blob. This was super enjoyable to read.

My only tiny gripe is that with the first quirk the author who insists that his implementation is bug for bug compatible lists the other implementations behavior and explains that they are very different from the original.

And then they proceed with additional quirks where the supposedly bug-for-bug compatible implementation also is different in the same way as the first example in that it produces an error message rather than the quirky output.

Don’t get me wrong: errors rather than quirks is much better behavior, but then don’t claim to be bug-for-bug compatible, nor roast other implementations for doing the same thing.