Security cameras are quite often placed at the entrance/exit. Having your device connect and making a DHCP request as you walk in seems like a legitimate concern.
Yeah, I get it. I just don't feel this level of caution is productive. If you aren't being currently tracked, then your concern is about whether someone can backtrack forensically and find you. I think a simple trip to a public computer at a library, particularly at a busy time, affords as much pragmatic anonymity as jumping through all the hoops described in the article.
On the flip side, if you are already are under suspicion, then all your efforts to anonymize a leak are in vain. You'll be the first person interrogated after a leak, and if your beliefs about the Orwellian nature of the government are true, the $10 hammer to the kneecaps (thanks XKCD) will undo any clever hiding you did.
I just don't think it makes much sense to go to these lengths. It's already understood that governments are corrupt. Are the specifics of what secrets you want to publicize worth the personal risk? If no, then you're playing spy, which is fine. If yes, then they'll probably find you if they really put their heart into it.
