Hmmm... this isn't exactly the tone I was expecting.
Not only does it not say much, they want us to buy their trust with that lopsided deal. There is no way we would consider such a trade, even if we weren't in a Tech Alliance.
Agreed. Although... rather than wait to send an indignant letter, we should send them a quick PM that we have to discuss tech trades with the team before accepting them in game, and we are sorry we did not accept their offer.
I know it sucks

to have to be nice to someone who has insulted you, but we are not yet ABSOLUTELY sure that we won't have them as the 4th ally... we just hurt ourselves by returning rudeness for rudeness...
In the last game, team Cav HATED team Kaz, because we were so arrogant, pushy, rude etc., but they never showed it, which kept the alliance intact. If they had been as rude as us, the alliance would have crumbled. Saturn on the other hand returned our attitude with more attitude and all it got them was a big fat 'L.'
They also didn't answer our explicitly asked question about their resources after telling them ours. Not a good sign.
Yeah that's pretty weak
It is possible that they are overestimating the value of having Metal Casting
I agree, they think that they have leverage because of MC but they will re-think that in 2 turns when we get Priesthood.
They don't have Sailing yet. They're the last team to get it. They at least didn't send a work boat our way. I think they've made a mistake not prioritizing exploration. The "two work boat wonder" is far cheaper... is available sooner... and our wonder keeps on giving.

The "Two Workboat Wonder"(2wbW)

... That's AWESOME

I think you may have coined a new Civ Demogame catch-phrase... Your analysis of the benefits of the 2wbW is certainly correct.
An important point, is that
since they don't have Sailing, they dont have Triremes, which means we can keep them from sending out workboats if we want, and they have no way of defending them. They really should have gotten Sailing by now for that reason alone.
Wow...That was the total opposite of the welcome we got from the other teams. Even Merlot did a 360 and was extremely eager to join.
See if I understand this correctly, they want us to give them a lot of stuff and don't want to give MC in return? Do they even realize what we have in tech?
I agree, and I think that in 2 turns when we get PH, their attitude may change a little, when they start to realize we dont need their techs.
That's even more presumptuous on their part, and bothers me a bit... it makes me a little angry that they'd offer that, honestly.
Looks like we'll have to send them a letter telling them we're disappointed just as we did with Merlot, although I'm much more disappointed by these guys.
I agree with this. We should put them on the defensive. TBH I think that their letter, coupled with their actions reflected a little bit more desperation than arrogance. They are trying to hard-sell us on the idea of us being allies because they know they are in danger of being left out. The correct play for them would be to offer MC and ask for a tech Alliance... but its easy for me to armchair quarterback from outside their team.
As far as the lopsided trade offer goes, I think that they are following the same logic that LP used when Saturn encountered the CavKaz alliance. He wanted a generous gifitng of tech to "demonstrate our good will"... he didnt get exactly what he wanted, and so ultimately Saturn joined SANCTA instead.
They want Sailing for Triremes and Writing so that they can tech Alpha themselves. No way we should give them either. Metal Casting is not worth giving them either of those advantages IMO. If they are not in the ETTT, then we should just blockade them.