Well, I don't know about you but I have watched Caduceus' conversations with Beau and Lucien about a dozen times each so let's compare and contrast.

So, the conversation with Beau highlights how far both of them have come since Caduceus joined the party. Beau is, dare I say it, downright gentle in her poking and prodding Caduceus' reactions. She's approaching Caduceus both from a place of concern and a place of equality; she doesn't feel the need to try to control the conversation or to find some angle to work. She pulls straight from Yasha's playbook back in the dance hall, making me wonder just how much of Caduceus and Yasha's conversation she actually got (that Observant feat is no joke, y'all). Beau approaches with a thank you for the healing, which by itself shows her growth, she acknowledges that she needed the help and is openly appreciative of it, then asks how Caduceus is doing. She gives him time and space to answer rather than impatiently jumping the gun, acknowledges his feelings, lightly prods his previous trauma, then finds a plan that everyone can presumably live with. She tries to speak Caduceus' language of fate, myth, and religion by harkening back to the Kiln and she lets him go when he’s obviously done. All in all, it is an amazing display of just how far asshole rebel without a cause, abrasive as fuck Beauregard Lionett has come. Props to her and Marisha.

But this meta is about Caduceus so let's talk about his growth. Because guys. Guys. If you need evidence that Caduceus has grown and let some of his walls down, this is it. He tells Beau he “doesn't like this” and goes as far as he can to explain what specifically is messing with him. Not only is this thing unnatural, it is a mockery of life. They are not alive, not truly, they go against everything he stands for. He expresses his desires clearly and plainly, “I want to burn it on the way out.” He acknowledges the rifts between himself and the others, then explains his thought process clearly and completely: that they are low on resources, that they might have to fight their way out anyway and the sooner they leave the better, and that he doesn't think the crest will just break. Anyone want to take a gander at the last time Caduceus laid out his deal like this? Trick question, he really hasn't. He has had a couple of moments where he talks out an idea but he rarely goes this in depth. Speaking this directly and specifically on his feelings and opinions just doesn't happen very often. For all that Caduceus believes other people need to talk about their feelings, he is very much a doer, not a talker, he doesn’t process that way. Caduceus doesn’t explain himself as a rule yet here he is, trying as hard as he can to make Beau understand. 

Contrast that conversation with his talk with Lucien. So, first of all, we know that Caduceus loathes what Lucien is trying to accomplish and has nothing but contempt towards the city and efforts to bring it back to the Material Plane. At best, Caduceus pities Lucien; he’s willing to believe that Lucien Knows Not What He Does and is being manipulated by the city. At worst, well, there’s always a plant that needs compost and Caduceus is more than happy to make some. He tells Beau this episode that “there’s something very wrong with your friend.” Yet Caduceus does what he always does when faced with an unknown, currently non-hostile threat- he starts with polite small talk. From the Gentleman to Avantika, from Ludinus to Essek, from pirates to stone giants to yetis, Caduceus’ default mode for dealing with threats is to play nice and polite and to figure out what information he can glean to use against them. People underestimate Caduceus right up until he reads them for filth and he totally pushes that polite, harmless image.

Now, I need some nervous nellies to pause and ask themselves why in the world Caduceus would “open up” to Lucien mere seconds after threatening the man. Because that is what his comment “I’ve never met anybody who looks like you before. For the record,” is. It is as close to a threat as Caduceus will ever utter. And if you don’t believe me, please rewatch the Roasting of Trent Ickithon and then watch this conversation again; Caduceus has the exact same polite bitch face energy there that he does here. Well, there, he was scolding Ickithon, here he is straight up warning Lucien. I also need you all to remember that conversation he just had with Beau, the one where he delves into specifics and keeps pushing himself until Beau understands where he’s coming from. This conversation is not that. Caduceus spends this entire conversation playing into Lucien’s expectations and dodging around his real intent up here. 

Actually, let’s talk about his ‘I’m confused’ bit here. He’s not confused about his ultimate goal. Caduceus has been driving the ‘we have to stop the Astral Sea City’ train from the literal moment it showed up. He’s the one who saw the Abyss stare back at them, he’s the one who insisted they ask Yussa, who asked Beau push her Cobalt Soul resources, who asked the literal Mother of All Nature for answers, who’s pushing for Essek’s help. Him, not the others. Hell, boy was asking Jester to ask the Traveler what the hell is going on, that is how anti-city he’s been this entire time. He knows what needs to be done, the question in the air is how. This changed because the Nein’s circumstances changed; they now have a crest and Lucien caught up to them much faster than they anticipated. Are they supposed to let Lucien summon the thing and take it out? Or is it better to wait for him to gather all the items and destroy them so they can never be used? What’s stopping the next guy from coming up here and doing the ritual themself? And what precisely is he supposed to do about Lucien and Molly? It speaks highly of Taliesin’s roleplay skills and the consistency with which he’s played Caduceus that Matt never once called for a deception check, despite the fact that Matt knows that Caduceus is directly opposed to Lucien and his goals AND is hiding that information. Taliesin and Caduceus danced so skillfully around that fact, it was a delight to watch.

Bottom line, Caduceus is very good at feigning vulnerability to get what he wants or to come off as a lesser threat. He told the Gentleman a bit about his worry for his family to induce the man to reconcile with Jester. He expressed his confusion and worry to the Nein and Essek at that dinner. Seriously, go watch those conversations and then go back to the Lucien conversation, it’s kind of eerie how well that playbook works. That pseudo-vulnerability was in direct service in getting the other person to do what Caduceus wanted them to do, it was not shared just because or in any real meaningful fashion. Both of those instances were direct manipulation tactics he learned at the Grove, comforting the bereaved. People are more comfortable sharing their issues and worries, after all, when you give them a little morsel of your own. People build a rapport around perceived sharing of vulnerabilities. People are more likely to do what you want when you have such a rapport. And that’s precisely what Caduceus did here; he didn’t tell Lucien anything Lucien didn’t know or couldn’t guess himself, he traded a small nugget about his own confusion for Lucien’s curiosity and it worked. The Tomb Takers and the Mighty Nein are stuck together for the foreseeable future and I for one can’t wait to see what growth awaits Caduceus next.

TL;DR: Caduceus has only ever been really openly vulnerable with the Nein, the rest is playing possum. Please don’t fall for it or worry that he’s actually unloading onto strangers when he’s actually unloaded quite a lot, for him at least, on his friends and loved ones. His growth is undeniable.