I mean, is it really so critical that the above post is viewable within seconds after I make it? Would it really make for much worse of a system if it wasn't viewable for an hour? Because that is a more fair evaluation of what would happen in a mix network. It isn't so much that you clicked the link to this thread and an hour later it loaded, and then you hit refresh and wait an hour for the thread to reload. It is more like you click the link to the thread and it loads right away still, but you don't see the post I just made for an hour or so after I made it. If you really actually had to wait an hour to load the thread after clicking it, or after refreshing the page, that would be super painful and nobody would want to use the system at all. But we don't need it to be like that. In other words, the hour delay isn't for you to view a thread, it is for the messages you make to be viewable after someone loads the thread. PIR allows for near real time *loading* of information, with very strong anonymity, but the best way to anonymize the *publishing* of information requires time delays. To reiterate again, viewing available data can be done extremely anonymously in essentially real time, publishing data extremely anonymously requires (in practice if not theory) significant time delays ~30 minutes - 1 hour , or more. Generally speaking it is safe to assume that the longer you delay the publishing of a message, the more anonymous you can be, but this isn't strictly speaking true, because the real issue is how many other people have sent a message prior to your sent message being made available. The time delay typically will correlate with the number of other people who have sent a message prior to your time delay expiring and your sent message being made available. I mean realistically, chances are most of the people reading this post are reading it more than an hour after I made it. If it took an hour for it to be published, you wouldn't be any the wiser. But I would have exponentially better anonymity.