That's because the AOO had all the most powerful mages, and dragons
weighed less and teleport limits were higher, so they mostly
teleported dragons. Plus, they usually won so quickly they didn't have
to blast much.
It's clear that most of the major alliances realized that aura blast
was important early on. Sir Codric, for example, had immunity from
aura blast when he was marching on my home castle. Too bad he also had
Transcend Death.
-- greg
[ so, how warm is it in Hades, anyway? ]