User blog comment:Supahbadmarine/Official Canon Policy/@comment-10514705-20130223075041

I feel I should throw my lot about now.

Cal's Responses:

How big can non-Imperil Interstellar empires be? - 50. Even then, I think that's pushing it.
 * Space Wolves Successors - No
 * Salamanders Successors - Not allowed a concrete link. Hinting at allowed.
 * Loyalist Traitors - No. That can of worms dare not be opened again.
 * Technology - Xenos should not be allowed to produce technology more advanced than DAoT stuff (unless there is a good, well explained justification for seemingly exotic technology). Human civilizations should not be able to develop beyond the realms of advanced Great Crusade Era Technology, nor be able to manufacture or reverse engineer DAoT on a large scale. Rare DAoT artifacts permitted only.
 * Dark Age of Technology - Should not be tampered with. It's a grey area for a reason. Mystery and stuff. Yeah.
 * Gue'vesa Astartes - No. Unless it has got a lot of justification and the Space Marines are working for the Tau with an ulterior motive (ie. double agents).