I’ve registered with the Guardian and I have never been blocked from reading a link I’ve found in the wild even if I am not logged in. I actually give them money because they, much more than other outlets, believe in the free information flow, low ad, mostly-text-based news that the Web was meant to be. If they are starting to prevent people from reading a link, even with a free account, that would make me less likely to continue my membership rather than more.