One thing I didn't think about the first time I saw the episode but that has stuck out to me every other time I've seen it is the connection between what happened in "The Andorian Incident" and this episode. I think the writers did a great job of tying the two together. For example, we learn that after P'Jem, the Vulcans have been keeping tabs on
Enterprise, and that the Ti'Mur isn't the first Vulcan ship they've caught lurking around. Vanik (or Douche II) says that if they'd actually been spying on him, Archer wouldn't have ever seen them. I wonder if that's true. Maybe they weren't so good at hiding as they'd thought and Archer caught the first ship by surprise. On the other hand, if that first Vulcan ship did intend for Archer to see them and then didn't respond, it really comes across as bullying and intimidation. Earth is supposed to be their ally, so why wouldn't they answer a hail?
I also think Trip and Archer (and maybe even Hoshi) are even more suspicious than they'd normally be about T'Pol receiving encrypted transmissions from the Vulcans because of the deceit and dishonorable behavior they'd recently learned the Vulcans were capable of. I wonder when Archer and T'Pol made that agreement about her not communicating with other Vulcans without notifying him. Was it at the beginning of their mission when they were ironing out the details of her dual-service, or was it a more recent development, after P'Jem?
Douche II was probably the most obnoxious Vulcan in all of Ent. Poor T'Pol! Just one episode before she'd been nervous about the humans embarrassing her in front of the monks at P'Jem, but in this episode the Vulcan is embarrassing her with his rudeness. I swear I saw her cringe a few times during that dinner scene! Does anyone know what Vanik said to her? Whatever it was, it seemed by her reaction that it was really horrible.
Trip impressed me with his behavior toward T'Pol throughout this episode. Archer was right: T'Pol never had to know that he'd read the letter, yet he chose to do the honorable thing. I think that's something we see with Trip time and time again. He's not all flashy about it, but he really is a gentleman and he consistently does the right thing. Archer's line about Trip needing to take a phase pistol when he tells T'Pol cracks me up. It may have just been a joke, but I think it indicates that the two men are very aware, even this early on, that T'Pol is capable of emotions like anger. My favorite part, though, is the scene in her quarters. When he tells her, "No, it's very relevant," regarding what
she wants to do about the marriage, I just want to stand up and cheer! I don't think she'd ever had someone care about
her wants before. (In "Home," we learn that even her own mother will steamroll over T'Pol's desires.) His obvious happiness at her decision to stay was so sweet, and I think that probably had a positive effect on T'Pol. Trip and Archer had both made it clear a few times that they found her annoying at times, and she'd already had some epic arguments with Trip, yet he made it pretty clear that he wanted her to stay aboard.

I have the impression that T'Pol had never had many real friends before, and here's Trip, reaching out to her in friendship. Alelou wrote a missing scene for this episode where Trip brings T'Pol the piece of pie we see at the end of the episode that I just love, and I've decided that Trip probably is responsible for that pie!
Finally, I really think T'Pol's decision to stay on
Enterprise instead of going home to marry Koss is directly related to P'Jem. While she may not have ever really wanted to marry him, I think she probably would have done the "right" thing if she hadn't just had her whole world rocked. I also suspect that Koss's high-ranking-minister father (or someone to whom he was answerable) was using the convenient pretext of marriage to get T'Pol away from those troublesome humans and back home where she belonged. If T'Pol and the humans hadn't just caused so much trouble for the High Command, I truly believe Koss's family would have granted her request to stay aboard
Enterprise for the greater good of Vulcan. I also think Trip was absolutely right when he implied she'd accepted the appointment to
Enterprise and requested a postponement because she subconsciously didn't want to marry Koss. I would like to know when exactly she made the decision to stay with the humans. I think she was torn in two directions right up until the very end. In fact, I would not be surprised to learn that when she made her transmission to the Ti'Mur that she was staying, that she had her bags all packed, ready to leave.