I'm pointing out that the context of "sparing Anduin's life" is unclear, since we've only seen the opposite. But it makes sense that Saurfang barely processes Anduin as an enemy. He sees him as a leader who is soft. His weak leadership was, in fact, what drove him to accept the war because he was convinced that Anduin might be undermined.
Anduin has thoroughly demonstrated himself to be the least effective High King the Alliance could possibly have. Saurfang started the war seeing others like Genn as the threat, not Anduin. That's just basic sanity. Anduin is no tyrant nor warmonger. He's simply someone unwilling to truly make hard choices himself. He's someone too scared to be seen as a tyrant to keep control of things in the long term. Too scared of wrongdoing to do drastic harm to the Horde outside of naivety.
Saurfang is unlikely to process Anduin as a relevant enemy. He isn't scared of people following Anduin's orders, he's scared of people not following Anduin's orders and Anduin letting them get away with it. Anduin is so willing to throw away advantages that killing him would probably hurt the Horde's chances of winning, especially since Anduin chose Genn as his current successor in BFA and Anduin would no longer be holding Genn's leash if that were the case.
I think Saurfang will be readjusting his sense of Honor. That's pretty fucking clear. But serving merely as balance to Sylvanas would feel hollow. Also, I don't think Saurfang would need to splinter the faction so drastically as you think. With the right moves, he could probably yank large chunks right out from under Sylvanas with minimal damage. Orgrimmar is an Orc city. There is no Siege of Orgrimmar 2.0 needed. Sylvanas knows her popularity is tanking, and she used Saurfang's popularity with the Orcs to drive the war.It depends from the actual justness of his cause. Will Saurfang ponder his actions and make them balanced enough compared to the situation he has to deal with? Will he accept the fact that his personal trauma is indeed an individual matter and not everyone would be of the mood to start a rebellion with the Alliance escalating the war effort? Will he try to serve as a just contrarian ideology balancing Sylvanas', or will he try to splinter the faction? Will he lead extreme actions out of genuine care for the Horde's best interests or for the sake of his idea of what the Horde should or should not be, two aspects that are not mutually exclusive but also not ever and always the same?
Calling Saurfang out as a traitor would demoralize her armies, the ones she used Saurfang to motivate. There might be no civil war at all.
Let's say Saurfang talks to Thrall and gets him onboard, while Zekhan acts as a rabble-rouser in Orgrimmar. Saurfang would now has tremendous political power, using both their reputations together. The current highest ranking Orc is Eitrigg, who would both be a fellow ranking Blackrock to Saurfang and a close friend of Thrall's. Do you really think Eitrigg would choose Sylvanas after hearing such concerns?
Fuck no. Eitrigg ditched the Horde for honor reasons before. He's been close friends with humans too, who were willing to turn against their superiors to save them for the sake of honor, so accusations of treason won't phase him much at all. Some of his best friends have been traitors, and he considered them all the more honorable for it. Eitrigg could then talk to his Mag'har buddies and likely get them on his side.
In such a short and simple move, through the mere power of speech, Sylvanas would find herself without a reliable power base in Orgrimmar.
As for Tauren? Saurfang would literally just need to walk up and say "Hi". If he already started building up political momentum, Baine would leap at the chance to join him and bring the Highmountain along too. As well as literally everyone else Baine himself may have gathered in his own private political talks. Continue with the momentum from there, a simple social revolution instead of a violent one, and there will be no need for a Siege.
The only challenge will be moving the Blood Elf and Forsaken stories to the right point.
Three lies will he offer you. I believe Anduin will face consequences, but not out of his malice. "Nothing, not even the King is more important than the Alliance" is lie #1. Anduin will prioritize his own morals over the safety of the Alliance. "I can't beat her" is lie #2. He can beat her, but he's unwilling to do what's necessary. He could beat her in weeks, but he doesn't want to. He let an enemy commander escape again, one who is likely to become his enemy in the future, because he was scared of dirtying his hands.It's not terror, it's nausea. From the way Anduin is developed and everyone always praises, excuses him or hold unconditioned and barely motivated faith on this guy, you know that no matter how dumb or retarded Anduin may act and look, the plot will bend itself at His Brightness' service.
And yes. Saurfang is likely going to continue the war. Is likely going to have to fight Malfurion and Tyrande again. Tyrande hasn't forgiven him, and Anduin seems to have kept Saurfang's release a secret. This moment is likely to be Anduin's eventual downfall, especially if he ends up wasting a perfectly good opportunity for victory because he's waiting on Saurfang.