In particular your paper discusses the "Tadpole" program developed by Rajib Karim to communicate with Al-Awlaki, albeit it doesn't refer to it by that name. It's interesting to see how there are different spins on the same event.
http://privacy-pc.com/articles/how-terrorists-encrypt-7-pecu...
Both papers point out that: Police described his use of encryption as “the most sophisticated they had seen in a British terrorist case.”
In the talk by Campbell, Tadpole is described as amateur hour. It's literally a Caeser cipher implemented using Microsoft Excel, with the results copied into password protected Word documents. Campbell observes that even a very rudimentary intelligence agency would be easily able to break this code without access to any of the underlying materials ... in fact, the technique for breaking such a cipher was first described by an Arabic mathematician over a millenium ago. This was used in preference to the "Asrar" PGP GUI that was circulating amongst jihadis, because it wasn't clear to Karim that Asrar was really trustworthy. Was it an NSA plant? This problem crops up all the time with jihadis trying to use strong encryption: they can't implement it themselves, they don't trust western apps and struggle to verify the origins of programs claiming to be written by fellow jihadis.
Overall Campbell treats Tadpole as a joke: a textbook study in why terrorists+encryption are not anything worth worrying about.
In the West Point paper you link to, the same program is described in quite different terms. It's described as an "intricate system", an "unorthodox and complex technique based on cipher codes and passwords stored on Excel spreadsheets" that produced "end to end encryption". It says "Western intelligence agencies were not able, as far as is known, to intercept any of his communications in real time". The West Point author appears to be under the impression that the only mistake Karim made was not wiping his laptop in time, which allowed police to access the underlying spreadsheets he was using.
This is a fascinating study in how the capabilities of terrorists are sometimes exaggerated to build the case for all-backdoors-all-the-time. Tadpole wouldn't have stopped a clever teenager with access to some intercepts, let alone an intelligence agency as sophisticated as GCHQ. Yet it is being used as evidence of fundamental shifts that require deep social and policy changes.