It's possible. Especially given the ISB is supposed to be tied more to COMPNOR, which is not military but civilian.
That's a new one for me, good pull. I've developed my own my own ranking structure for the Star Wars galaxy which I believe fits the scale required while conforming to most of what we have seen/read thus far. It's my belief that Tagge holds the rank of Grand General (an Army rank) and was at one time appointed as the Supreme Commander of the Imperial Military. Grand Admiral is a rank, but there's no firm role for them. They can be posted to any position, office, or billet as required. The only persons in a position to re-task them would be the Supreme Commander, Chief of the Navy, or high ranking "civilian" (Emperor, Vader, Grand Moff). I don't really see Vader as ever being subordinate to Tagge or Tarkin. His rank and position is outside of both the military and civilian command structures. Basically, he does what he wants and the Emperor lets him do what he wants until he feels Vader has overstepped his bounds and he brings him back to "Earth". That said he has a certain level of respect for people such as Tagge and Tarkin, a working relationship if you will. Vader's objectives were either given to him by the Emperor himself or were long-game goals for the greater good of the Empire. I didn't mind the position of Military Executor for him, but I don't he would want to be Supreme Commander as this would have massive administrative responsibilities. In my mind Vader was an enigma: apparent 2'nd in command within the entire Empire, holding no military rank but able to command forces as he wishes, operating as the Emperor's agent in covert/one-man operations, having command of the quasi-military forces such as the Inquisitrious, while also able to interact with the Imperial ruling council, government bureaucracy, and civilian command (Governors, Moffs, Grand Moffs). No one knew what he was supposed to be doing and no one was brave enough to ask questions, which was exactly how the Emperor wanted it.
I think Vader always acted as the Mouth of Sauron. He's always speaking with the Emperor's authority but never his own. It's something which changes after the comic book and ANH.
Yeah, it doesen't make much sense for Grand General to be supreme commander. Rather appointed supreme commander. As for these Chief positions, I doubt they give any more power. The only proof we have and most likely outcome is that they are just to advise on the joint chiefs. Motti v Thrawn? edit: On a second thought, what if basically it is some form for hint that they're actually doing the Grand Admiral & Grand General outside the regular hierarchy? Motti and Tagge were Admiral and General. So they are the leader of the branches while Grand General and Grand Admiral works outside of the normal structure? This pattern sort of breaks, because there is fleet admiral inbetween admiral and grand admiral. And how would the grand general be outside of the hierarchy? Grand admirals are allowed their own fleet and rove around, others don't. So what's the grand general feature? What about the fleet admiral? Either they just work as simple advisors, or we need a couple of questions answered.
Grand Admiral and Grand General could be akin to a 5-star rank. https://en.wikipedia.org/wiki/Five-star_rank This could be a military rank that puts them on par with a Grand Moff who runs an Oversector or Priority Sector.
I do like how the Grand Admirals and presumably Grand Generals undermine the joint chiefs. Also, are we sure that Tagge is in charge of the Army? The only thing which suggests that is the title of General but every one of his conversations is about fleets and Naval operations. TIE Fighters use Army rankings, so it seems more likely he's Air Space Force than Army.
I think something people forget is the Theater Commander. Like Eisenhower in WWII. Supreme Allied Commander Europe. He was an army general....and had command of all forces...US and Allies. Army, navy, etc... That could be something that distinguishes the Grands.
Well, Palpatine's plan in Darth Vader is that he's grooming Vader for promotion to the Empire's Supreme Military Commander a.k.a The Legends Executor equivalent. Tagge is a placeholder until Vader gets his shavit together.
What's the problem with separating rank and command? I agree that it would be nice if everything was logical in the rank/command structure (and it's not even that hard to figure out), but it's clear this was not made a big priority in the EU or the new canon. So we basically have to assume that in the Empire, a persons command and rank could be unrelated in that they could be posted to any command regardless of their rank.
It would be a split between Tarkin and the Grand Vizier to me (and Sate Pestage will always be the Grand Vizier in my mind haha). Tarkin being the Grand Moff of the Outer Rim Territories and the Grand Vizier who effectively ran the Imperial government.
Albeit, Mas Amedda doesn't actually have any authority not borrowed from Palpatine as we see in Empire's End.
I haven't read Empire's End yet, but in general the rank of Grand Vizier and Mas Amedda hasn't been portrayed as having the same importance as in the EU, IMO.
Isn't Mas Amedda the type of guy to argue with Tarkin? (Didn't that happen in the book Tarkin?) Meaning grand vizier v grand moff is still debatable.
As I see it, the surviving Imperials decided not to listen to him after Palpatine's death in spite of his legal authority.
I should clarify my opinion because in Tarkin the Emperor says "the three men who would shape the Empire" or something very close to that. So in canon, yes Tarkin is 3'rd on the totem pole. But in the EU, I think it could have been debated whether Tarkin or Sate Pestage had more power within the Empire at the time of ANH.
I don't think Mas Amedda has any legal authority because Grand Vizier is not Vice President or Vice Chancellor. It's more akin to the status of Chief of Staff. He's an advisor to the King rather than an actual person in the royal line. Technically, the Emperor's successor should have to be appointed by the Senate or Emperor himself, assuming a Roman "Four Good Emperors" situation. It's just Mas Amedda was the highest ranking Imperial after the death of Palpatine.
Star Wars: Absolutely Everything You Need To Know had him holding the position "Chief of the Imperial Army": http://starwars.wikia.com/wiki/Chief_of_the_Imperial_Army though the Databank said "Chief of Military Operations aboard the first Death Star": http://www.starwars.com/databank/general-tagge
I'm not disputing anything you said but I'd like to point out there are two different questions being asked. Who had the 3'rd most power in the Empire after the Emperor and Lord Vader (assuming they are alive and well) and who might have taken over leadership should they both be killed. Vader would have probably taken over had the Emperor died, although I think that would have been a mess. I don't think he truly wanted to rule the galaxy although he says he wants to twice in film so maybe I'm wrong.
From Rogue One: Mission Files, on Tarkin: Spoiler Only the Emperor himself has more influence over Imperial policy or has done more to bring planets under Imperial rule. (Cracken, to Mon Mothma)
This makes sense. With the possible exception of Amedda?, no one in the Empire has more power than Tarkin save the Emperor himself. Even Vader to me, for all intents and purposes, seems like he's Tarkin'a equal or subordinate. But never superior.
Yes and no. The Grand Vizier and the Imperial Ruling Council are, if anything, more prominent than they were in the EU. It's very clear they run the Empire. The difference is that this time, the civilian leadership doesn't have the support of the military once the Emperor dies. They're important. But nobody cares.
I think, IF Tarkin is supposed to be the third most powerful man in the Empire, it is not because of rank or official position. It would be because of Tarkin being a man of the Empire's first hour, his influence on Imperial Doctrin and later on because of his contributions to the expansion of imperial rule. In regards to the administration of the Empire Tarkin is, what the Grand Generals and Grand Admirals are in regards to the military - mini-Vaders, people directly appointed by Palpatine and superordinate to the bureaucracy and military outside the regular chains of command either on a case-by-case-basis or constantly, where they only become involved as soon as their intervention is required or their interest is captured. Officially the hierarchy would be Palpatine - Amedda - Ruling Council, while Vader, despite his status as potential crown-prince is little more than a gloryfied errand-boy so long as Palpatine is alive (officially, of course few would dare say "no" to Vader without the assurance, that Palpatine would back them over Vader).
