User blog comment:Vivaporius/AT Idea: Imperial Civil War/@comment-2253300-20120407031354/@comment-3398633-20120407161134

Exactly. Also, the Astronomicon was built during the Great Crusade, meaning there was no need for it at the time. Plus, you have to remember that there no Astronomican during and after the DAoT, but there was still plenty of space travel. I can see how the Imperium has developed something of a dependance on the device, but not a permanent one. Just my opinion.