I already suspected DCF wasn't really together with the rest of t h e makers of Trek on this. I'd heard she'd meant the Romulan Commander and Spock to be falling in love for real. Then I heard the opposite though, that it was people besides her pushing for that change to her script. And if she's announcing Vulcans just simply fall in love just like other peoples, then she's never paid attention to This Side of Paradise and many other episodes. In fact , she's missing the point of what Vulcans are.
Unless you know some behind-the-scenes thing that I don't, Theodore Sturgeon wrote Amok Time, not DC Fontana. And if she's right, pon farr has no meaning except as an excuse for a few action scenes. It becomes a bad episode.
I'm a Trek FM fan and the podcasts talk about DC Fontana a lot more than Sturgeon. My mistake. But later, we see or have implied evidence that Vulcans have sex outside of pon farr. There's T'Pol in Harbinger and some of Tuvok's kids are less than 7 years apart. Is that a continuity violation to you?
Really, not limiting sex to every 7 years makes pon farr an excuse for some action scenes? To me the interesting part was seeing the normally calm Spock not having everything together. And the shame surrounding it. A little mystery doesn't hurt. For the record, most of us who agree with Fontana consider Amok Time one of the top episodes of TOS.
Here's a good summary of pon farr throughout all the shows.
http://www.ex-astris-scientia.org/inconsistencies/biology-other.htm
As for Romulans and pon farr, I think it can go either way. Nothing in the shows or movies ever addressed this.