Revealing that Saul Tigh (Michael Hogan) was a Cylon undercut his evolution as a character, and Ellen Tigh (Kate Vernon) turning out to be a Cylon retroactively robbed her death of any meaning.
Boxing a Cylon is quite literal ... and her performance helped make Number 3's evolution believable. Just before she's boxed by John Cavil, she has a look in her eyes that she's accepting her ...