Breton wrote:
The other thing people are missing is that
GW has said that the battles we fight are just one small piece of a larger war. They didn't do subfactions right for some armies - especially orks and guard - But their description of our battles is basically a strategic point held by the Cadian 327th against an assault from just a small Goff portion of the WAAGH! At the same time the Space Wolves were going after a Genestealer cult, the Sisters and Guard were fighting some Orks, while the White Scars were taking on Speedkult orks elsewhere, and the Ravenwing were off on one of their agendas, and Marneus was duelling Abbadon
Certainly this is true of a great many battles in the
40k lore- maybe even most of the battles.
But the fact that Torchbearer Fleet and War of Faith Crusade rules exist very clearly communicates that sometimes armies of multiple factions do fight side by side by side to achieve shared objectives.
What's missing is the similar rules for some of the other factions. I fully expect guard and chaos to have exceptions.
Either way, this change is very, very specifically a Nachmund Gauntlet Matched play game rule. If you take a Matched play mission from any other book, the rule literally does not exist. If you play Crusade or open, the rule literally does not exist. I was extremely worried before we saw the actual details of the way this change was implemented, because it had the potential to be written in such a way that it impacted the entire game. As it turns out, the way the rule was implemented limits it's impat even beyond what I had seen as a best case scenario.