I take it back; the delay is long but limited, and external stimulus doesn't really make a difference AFAICT.
http://www.ubuntuforums.org/showthread.php?p=1329214#post1329214 shows details, including an excerpt from /var/log/messages, which I've attached in full here -- Long delay during "mounting root filesystem" at boot https://launchpad.net/bugs/54797 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
