Much to my own surprise, I’m a complete sucker for this budding Spock/Chapel romance. I just want these two beautiful people to be happy together, damn it! We all know it’s doomed, unfortunately, and I hope that whatever inevitably destroys it doesn’t turn out to be too painful for the characters involved. Spock and Chapel are obviously not engaged in a romantic relationship in TOS, most obviously in Amok Time when such a pairing would have rendered the entire story trivial.
Someone mentioned in a previous thread that Spock’s Pon Farr (seven years before Amok Time) is closing in. I was skeptical in that thread that they would choose to touch on it then, but the events of this episode do make that seem quite a bit more likely, if (again) increasingly difficult to square with Amok Time.