Zarhym speaks about Lake Wintergrasp on the Warcraft Forums:

Clearly that hasn't been the case, but we've learned how the design and appeal of the zone can lead to performance issues if too many players are crowded into a relatively small space.

Are you kidding me?

There's a reason why past world events have had issues. Especially concerning the invasion when the Dark Portal was opened. One reason why the second invasion (just before the launch of the Lich King expansion) was "spread out" was to lessen the lag caused by too many players in one place.

I've been playing for about three years now and I can't recall a time when players were not aware of what happens when too much activity occurs in one place.

Are we seriously expected to believe that only now does Blizzard realize what happens when too many players are in one zone?

Color me boggled.