Definitely black propaganda. None of this comes from GCHQ. The original for the first part of the document is on DailyPaul [0], published in 2008 (before the alleged Cryptome 'leak' in 2012.

Reddit user /u/itsnotlupus found more sources for the rest of the document. [1]

[0]: http://www.dailypaul.com/60831/techniques-for-dilution-misdi...

[1]: https://pay.reddit.com/r/conspiratard/comments/wzg2i/i_think...