A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
In reference of this topic: viewtopic.php?f=59&t=59082&hilit=
How does it work now with the SE wording of Determination?
Determination: Dark Virtue Reaction: Before you announce an action, target one of your Samurai: The action can not have its effects negated or have its targeting changed. After the action destroys any Personality, remove him from the game.
EXCEPTION: “Cannot” and “Can only,” when referring to entering play or attaching, are restrictions on the legality of entering play or attachment.
Likewise, the phrases “cannot” or “can only” appearing in rules text apply to the legality of doing something in the first place; they do not imply that doing that thing is merely negated.
[Edit - Corrected as Roger clarified to me what "rules text" meant]