1.
In complex systems it is to expect that some elements will meet other elements and will create unusual interaction.
Parsimony of Seclusion and Dragon factions.
Peculiarity of Crown of Flowers that allows to discard (along with the card) other cards, otherwise hard or impossible to discard.
Carambor and Healing of Nimrodel.
Here, There, or Yonder, Under-deeps, and ally normally not allowed to move to Under-deeps.
(I would add Thrall of the Voice and characters with a race other than a race that normal character would have)* .
There is nothing wrong in searching for such interactions and using them. Necessity of errata does no come from mere fact that some combinations or uses was not planned by authors. But the searching should be done fair. Carambor does not (necessarily) interact with Hall of Fire as he interacts with Healing of Nimrodel (unless according some interpretation of rules his company is at site between its subsequent M/H phases).
2.
To the topic of Armory itself.
dirhaval wrote: ↑Fri Feb 09, 2024 7:07 pm
Depends on site. Sting cannot be played from Armory it said item is in play. There are still checks. Rebuild the town can allow hoard minor items. Good way to keep items away from opponent, emerald of doriath, thrors map.
I am not sure what exactly you are speaking about, but you have mentioned unique minor items.
I think that situation when Sting is under Armory and its other copy is in play at the same time would happen only if Sting under Armory would not be considered in play even for purposes of uniqueness.
Stored cards are considered as not in play except for purposes of uniqueness. So this situation would happen only if cards stored under Armory and cards placed from hand under Armory would be treated differently.
*) ROC recently decided otherwise but I do not think that Thrall of the Voice supersedes "You may not play Orc and Troll characters until you have played the appropriate card (e.g., Bad Company)."
It does not supersede the rule, neither explicitly or implicitly.
Thrall of the Voice is just one of the appropriate cards.