My guess is that at ArsDigita they ran AOLServer as root (bad!)
I'm not sure how you reached that conclusion. AOLserver 3.x takes a user and group parameter, which is uses to release priviliges after it acquires port 80. aD ran these servers as the 'nsadmin' user. AOLserver 2.x had a "User=whatever" parameter in the config file that it used to downgrade itself from root after binding to port 80. We also ran the 2.x AOLservers as the 'nsadmin' user.
I'm only guessing here since ArsDigita had
documentation on how to run it on a chroot environment
chrooted environment doesn't necessarily imply running the server as root. The thought was that shared sites on a machine would be chrooted, so that if one instance got hacked (whether due to aD or customer fault), the other instances would be somewhat safe. It was more CYA than anything. Inside of the chroot jail the AOLserver ran as nsadmin. I don't recall how widespread we actually chrooted customers (if at all)
(which I did once, but
it was more painful than useful)
amen to that brotha! The Solaris truss command became my best friend in figuring it out.