Originally Posted by
Morbownz
Well, since Nostalrius was up for over a year without AQ40 or Naxx available not to mention all the other private classic realms that have been around for a long time (--SNIP-- realms have been around since 2010), I'd say yes, it's already been proven that they could last over a year.
You're also ignoring the fact that most of the players these realms could appeal to would be players that never played classic, so it could potentially be new to them.
Finally, having played on several classic realms myself I can say from experience that most reliable information about class mechanics is sparse and not always easy to understand since most information is in the form of indepth class discussions on EJ.
Most of they players I met relied on the simplest of information such as BiS lists, so when it comes to endgame content things like managing resources (Mana) has a learning curve. Whether it's as hard as Mythic raiding doesn't matter, if it's enjoyable (which Nost was for many people) then it can work.