Mouth of Sauron?

[Inziladun]

My position is that Sauron did not allow his servants to use any personal name for him under normal circumstances, probably due to a desire to be as impersonal to his minions as possible, befitting the "king and god" status he wanted to have with them.
When dealing with his enemies, however, the use of a name was required. The Mouth wasn't the first one to do it apparently, either.

'Then about a year ago a messenger came to Dáin, but not from Moria--from Mordor: a horseman in the night, who called Dáin to his gate. The Lord Sauron the Great, so he said, wished for our friendship.'

That was Glóin speaking to the Council of Elrond.

So, when Sauron dealt with those he didn't command, he had to use a name, and I think 'the abhorred' was probably not something he particularly hated; on the contrary, he would likely have been proud of it.

[Nerwen]

Originally Posted by Puddleglum

I'd guess it was an oversight on Tolkien's part (one of few) - unless we hypothesize that the Mouth was so high in Sauron's favor that he was allowed to use the name. In that case we could say that Aragorn's information was not 100% correct (perhaps he had only before encountered servants of Sauron that were not permitted to speak/write the name).

Originally Posted by Inziladun

My position is that Sauron did not allow his servants to use any personal name for him under normal circumstances, probably due to a desire to be as impersonal to his minions as possible, befitting the "king and god" status he wanted to have with them. When dealing with his enemies, however, the use of a name was required.

Also, there's the matter of context: the three were hurriedly trying to work out the allegiance of the Orcs bearing the "S" insignia. Aragorn (and the author) might have thought it irrelevant to mention any such exceptions to the rule at that point.

Whatever the details of Mordorian etiquette, I don't think this concept (that Sauron's servants avoid using his actual name) is just a "freak", brought up in that one chapter and then forgotten. The various Mordor Orcs we meet do go out of their way not to say it, instead substituting "The Great Eye", "Him" etc. (Gollum, who also talks like this, can be presumed to have picked up the habit in Mordor.) It's true that the good characters aren't too keen on using Sauron's name either– there's obviously some kind of "speak of the devil" notion in play in Middle-earth– but they're not nearly so consistent about it.

[Galin]

Yes I agree with Inziladun and Nerwen.

In my opinion Aragorn need not mean 'not in any circumstance whatsoever'; he was speaking generally and in reaction to tokens on orc-gear, and is correct enough without adding something like 'but there may be some instances in which Sauron might allow...'

I think this is just realistic conversation given the situation.

[Morthoron]

Well, the Mouth of Sauron couldn't bloody well have a conversation like...

MoS: I am the Mouth of...ahem.

Gandalf: Beg pardon? The Mouth? The Mouth of whom?

MoS: You know.

Aragorn: Ummm...I am afraid we don't.

MoS: Oh come on! Him -- you know -- HIM!

Gandalf: You are not being very clear.

MoS: You know, the Big Guy.

Aragorn: Is he referring to a Troll?

Gimli: Could be. Troll's need someone to speak for them.

Legolas: Aye, they are very inarticulate.

MoS: No, no, no! I am the Mouth of Sssssss...of Sssss...oh damn!

Gandalf: Sssss?

Pippin: Sam!

Gimli: No! What would a Hobbit need with another mouth? They have one too many already!

Gandalf: This is getting us nowhere. What we need is someone who can speak for Sauron.

Pippin: Why, can't he speak for himself?

MoS: Sighs...

[Khazad-dûm]

Perhaps at the time when Aragorn said 'Neither does he use his right name, nor permit it to be spelt or spoken...' at the time Sauron was still building his power and armies trying to be as secret as possible. Then by the time they speak with the Mouth of Sauron (third book) its already obvious that it's him so why pretend it's not.

Here's something out of the Encyclopedia of Arda that I base my statement on.

"One possible reason for Aragorn's error is that his information is out of date. For most of the Third Age, Sauron had been building his strength, in secret, at Dol Guldur. Given his need to remain hidden, it's natural that he would ban his servants from using his real name. Any detailed information that Aragorn had about him and his ways would date back to Gandalf's spying expeditions in this period."