Earlier quoted context omitted.
As I read it, the writing is un-decodable because it's not really "writing" in the conventional sense, it's recipes encoded using single-letter abbreviations, many of which require an index to decipher. No index is present, and the author surmises that it was never completed, or lost.
I'm reminded of the work that was done to reverse engineer the Intel ME 11 [1], it was compressed with an unknown Huffman code which the team was nevertheless able to recover somehow. And that was with variable-length words! [1] http://blog.ptsecurity.com/2017/08/disabling-intel-me.html
> In particular, MINIX was chosen as the basis for the operating system (previously, ThreadX RTOS had been used). Now ME firmware includes a full-fledged operating system [...]
Woah, did I read that correctly? That there is a version of MINIX running inside of the Intel processors of presumably almost every modern computer with an Intel CPU that has Intel ME in it? If so then that's insanely cool! I mean I still dislike Intel ME itself and wish I could disable it easily and without risking damage/destruction but the idea of there being a version of MINIX running on my computer right now is quite cool.