Quite. I was surprised by how many people (and reviewers like those at A.V. Club) thought she genuinely converted and yet found that idea implausible. While she's been shown less of a political maneuver in the books (simply because we largely see her time in King's Landing from Cersei's perspective), Margery has always been presented as more formidable at the Game of Thrones than Cersei.
If the same scene occurs in the books (which would only happen if we start getting perspective chapters from either of the characters), I'm willing to bet the message would be text based simply because of the narrative medium.
If the same scene occurs in the books (which would only happen if we start getting perspective chapters from either of the characters), I'm willing to bet the message would be text based simply because of the narrative medium.