If a unique character changes control (for example, Reek) that character may have attachments or duplicates attached. Attachments, unless changed control, still address their original owner ("you"), naturally. But what about duplicates? On being played, the rules state, they cease to be any sort of attachment.
As duplicates are used as a save response, their use must be activated (a triggered effect?). Therefore, the question is whether the character controller chooses whether to use a duplicate or does control of the duplicates remain with the character's original owner?
I am pretty sure that saves with dupes are an action taken by a character's controller and therefore the original owner does not make the decision about the use of the dupes s/he stacked up on the character. However, I feel the need for some KTom validation.
Winter.