I'm actually inclined to agree with your position, at least to a point. However, P4 beta pulled in record numbers, and there is the possibility that until that point they really didn't realize just how much people would want to play. Given that there's a week between then and now there may have not been enough time to prepare. Add to that more people in EA, and likely more in Launch coming up... well we'll see how they handle things.

Having said that, I'm inclined to believe you scenario more
P.S. they have experience running FF11 too so, yea I think they could have seen this coming.

Just remember though, server admins have it rough, never enough budget to do the job right (coming from a soon to be admin with a degree in computer science)