They AT LEAST are "keeping" it in the Sacred Realm, and probably had exclusive control over the keys to the entrance at some point given that you need the song of the royal family to access the Spiritual Stones (Fire and Water at least, since you don't have Zelda's Lullaby in the forest).

Lex, do you believe the royal family was in control of the Triforce pre OoT?

Just gotta say, I love the avy.

As you probably know, I think that Link returned to the past after Ganondorf was already in the Sacred Realm and closed the Door of Time, sealing him inside and sealing off all of Link's previous travels through time from the new history. This would inevitably mean that Ganon would touch the Triforce, causing it to split and giving the three bearers their crests. It would also mean the creation of the Dark World. The "something outrageous" could have been the destruction of the Temple of Time/spread of darkness that would surely have accompanied Ganondorf's attempts at escape. The darkness would have been sealed, thus the Sages' Seal, but Ganondorf himself was executed, as seen in TP.

Can you elaborate how this would/could happen?

I don't really care where TMC goes, as long as it's after ST and before FS/A.

So you're thinking TMC-LoZ-OoX-FS/FSA?
Eh. I gave up on the timeline a long time ago. Personally I can see it going three ways now.

On the mirror thing: I'm not exactly sure where I place FSA at the moment, but if I place it after TP I go with the idea that there's more then one portal to the Twilight realm.

If an expressly-CT game ever gave any indication of:

1) a Sages' Seal being cast between OoT and TP (or after TP)
2) a new dark tribe being sealed in a new mirror
3) the Four Sword existing on that timeline

I would probably change my timeline. Of course, explicit reference to the events of a 2D game would be nice, but doubtful. I'm not positive about where LoZ and OoX specifically go on my AT at present, either, although I'm guessing before LttP and probably before FS/A.

Do you ever think of changing your timeline?

More evidance for your removed TP thing theory: