Yes, personally I can't understand what the big problem is.
I would think that the server side of war is similar to wow that is a sql server. Database servers are extremely scalable due to the nature of the tasks they do.
Anyway, what would make the problem much less would be to balance abilities. I have a sneaking suspicion that the prevalent use of disabling abilities on a massive scale is the prime problem since it requires a lot more data to keep tabs on especially since they don't work as they should.
They claim this is the "first step" and will be replaced by better actions. But the question remains, what is the selling point of war compared to wow?
Open large scale rvr.
Since keeps are useless as they are, no one usually cares to defend them, and bo are indefensible where and what should the orvr be?
By limiting the only remaining large scale orvr to a select few people, I suspect that they will instance them and give priority to warbands on the average of the rr they have. Thus limiting the rvr to the absolute minority in the largest guilds on the winning side.
Nothing will ruin a game more than exclusivity.