Poor choice words I suppose - I'd much rather be submitted to the "killing fields of the experimental method" than the actual "killing fields" of a Communist regime.
Eh, I think you're being a bit dismissive. There is a consistent "voice" to the memos that gives them authenticity, and a sharp business insight that no one working in PR would be able to articulate. Yes, I'm sure the letters are parsed by PR and legal, but I very much doubt that they contribute much beyond basic editing and fact checking. But of course, this is all speculation.
https://en.wikipedia.org/wiki/Khmer_Rouge_Killing_Fields