Board Thread:Warhammer 40k General Discussion/@comment-24821739-20140604204305/@comment-184.96.176.105-20140605214914

The Imperium at the moment may be far too corrupt to restore itself. The High Lords of Terra are all slightly tained by Chaos and the Ecclesiarchy is just a gigantic ruin, it was proven to be ineffective when the Age of Apostasy almost destroyed the Imperium. If the Primarchs do come back they will remember the Imperial Truth and seek to turn the Imperium around back to the Imperial Truth. However they will encounter extreme opposition which could cause a devastating civil war which will collapse the Imperium.

While I also doubt the Emperor can return. The Starchild theory is possible. But if the Emperor's energy forms a god of order the god of order will be overthrown by the Chaos he faces in the warp.