The so called hackers have to be dissuaded about sharing personal details in the chatrooms? This document looks like the proof that these groups are made of regular kids more than security experts in my opinion.
Not really. These things are hard to get right and stick to for prolonged periods of time. This requires practice and discipline.
Ordinary people (and even trained professionals [1]), get sloppy and make mistakes. Thus, this line from the presentation is golden:
"Amateurs practice until they get it right, professionals practice until they can't get it wrong.
[1]: Another excellent essay by the same person - grugq (of +HCU and Fravia+ fame) on the major OPSEC fuck-up by CIA in Lebanon and the factors that likely have lead to the full compromise of a big informant network, and possibly the deaths of a number of people [2]: http://grugq.github.io/blog/2013/03/12/anonymity-is-hard/
added: even small things like complaining about freezing your ass off due to the cold weather, accidentally linking two nicknames, emerging at regular times (synced with a specific timezone) could be used to uncover your identitiy. As evidenced, slip-ups like could get you in jail. You can check the discussion from a few weeks back about the hassles of creating a truly anonymous page on Internet: https://news.ycombinator.com/item?id=5638988
