Earlier quoted context omitted.
There are certainly a lot of DefCon attendees who think that this describes them. In my observation they are all very incorrect, usually humorously so fortunately.
My first thought was that GP was saying DefCon attendees would be counting cards, which is an effective and legal way to beat the house[1] (until you're caught and banned from the casino). 1. https://www.freep.com/story/entertainment/nightlife/2016/04/...
Statistically, it is not effective. Your card counting needs to be (basically) perfect, and you need very deep pockets to handle extended drawdowns.