What the filmmakers did was put Willoughby’s claim of honorable intent (44) into Brandon’s confession because they could not work Willoughby’s confession into the film (The S&S S&D, page 272).

I understand what you are saying, but I can't help thinking that it makes no sense to put words that could (and probably should) have been said by Willoughby into the mouth of Brandon, of all people. Even setting aside the fact that it is unfaithful to the novel, this change makes no sense in terms of the story. Why would Brandon make the effort to explain to Elinor the extent of Willoughby's villainous behavior toward Eliza II - behavior over which Brandon has every right to be furious - only to later remark that, essentially, Willoughby wasn't so bad after all, and in fact had "honorable intentions" toward Marianne? I can't see the Brandon of the novel making this sort of statement; judging by his righteous anger over the horrible mistreatment of his ward, can you see him giving Willoughby ANY credit for good intentions? Even if Willoughby DID mean to propose (which I doubt), good intentions by themselves are practically meaningless. Jane Austen's Brandon is a man of sense, and would be well aware of this.

Furthermore, how would Brandon in S&S2 have known that Willoughby intended to propose? I can accept that, in S&S2's universe, he could have gotten the information from this "Lady Allen" person (Mrs. Smith), but note that S&S2's Brandon doesn't merely say that "Lady Allen" told him that Willoughby had informed her of his intention to propose to Marianne. If S&S2's Brandon had said this and nothing more, then at least it would have been objective and honest, but, no, he oversteps his boundaries by stating that he "feels certain" of Willoughby's intentions to marry Marianne. S&S2's Brandon is relying on secondhand information - how could be be so "certain" of Willoughby's "honorable intentions"? And why would he bother to mention this at all?

AR’s Brandon shows Willoughby to be weak and unsympathetic by almost saying the obvious; that he chose fortune over Marianne.

This is an interpretation I hadn't considered before, so thank you for putting it forward. So instead of being too sympathetic to Willoughby, this remark of Brandon's is just a cheap shot at him? That makes S&S2 Brandon look extremely petty, actually. (:D)

Exactly how do you see the filmmakers of S&S2 unknowingly put themselves into a potentially difficult position?