Well the date of the announcement was set by outside factors (specifically the date of the con).
But I am sorta surprised we haven't had a "this is our vision" sort of vague DD like they often do.
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But I am sorta surprised we haven't had a "this is our vision" sort of vague DD like they often do.
IIRC, they try to avoid too many overlapping DDs. AoW is coming first, so that is getting DDs first.
Oh, the release of AoW is gonna be way earlier than CK2 Charly? Didn't even know that 
o
o
I think Paradox had no idea how much work a scenario in Charlemagne's era actually would need. And when the fans pointed it out they thought: "shit, and we thought we were almost done". That's why no DDs, and why we get the streams where Paradox learn how CK2 won't work in multiplayer instead. There are more work to be done than they anticipated.
There is absolutely no evidence that Charlie was ever delayed. Since the release, PI did not go around promising any new info, even before we saw enough to conclude that much has still to be done with the scenario and from the very start they said that the expansion is in a very, very early phase.
As for MP... why do so many people here forget that at the very start of the session PI said "Let's pray that the game doesn't crash too soon!"? and talk as if the instability surprised PI? Seriously, they said multiple times themselves that MP was still unstable and that crashes were expected, yet people here forget about that all the time...
The reason that Charlie was so early announced was so that they could show something at that Convention, that's all there is to it.
The only items that I wish Paradox would share are: the de jure maps at all levels, the political map and the cultural map - with the understanding that these are WiP. I realize that there are bits and pieces we can kluge from the streams but releasing what there is now would allow a lot of our input to be considered at an early stage so perhaps changes could be made and tested earlier.
And we do get some tidbits in "devs play". It just takes some detective work which is enjoyable. For example, I got answers to what religious group Zun are and is Vandad Hormodz playable.
I doubt they don't know...
They simply want to announce it at game convention thus reduce the need to go directly to news site to promote their DLC...
Much like how they announce Wealth of Nation way too early (only about two weeks after Conquest of Paradise, if I am not mistaken) and took several months before they gives any DDs...
Also, CoP DDs were halted (or slowed down) as SoA DDs start (CoP release date even get delayed, though I think it is technical issue instead of don't want to release in the same date as SoA)...