Okay, I for one am getting sick of this adding the whole YMMV to Roboute Guilliman being a Jerk With A Heart Of Gold. I've read the stories in Age of Darkness as well, and I agree that something is definitely fishy. But what I also interpreted was that Guilliman was making these plans to save the Imperium from complete collapse. The only source which says that Guilliman was trying to replace the Emperor was Lion El'Jonson, who has a rather questionable record on this himself. If it's really about questioning whether Guilliman was the Starscream, then put it under Alternate Character Interpretation in the YMMV section.
Okay, I for one am getting sick of this adding the whole YMMV to Roboute Guilliman being a Jerk With A Heart Of Gold. I've read the stories in Age of Darkness as well, and I agree that something is definitely fishy. But what I also interpreted was that Guilliman was making these plans to save the Imperium from complete collapse. The only source which says that Guilliman was trying to replace the Emperor was Lion El'Jonson, who has a rather questionable record on this himself. If it's really about questioning whether Guilliman was the Starscream, then put it under Alternate Character Interpretation in the YMMV section.