Maybe releasing modules is good for keeping punters happy, but it's a crap way of developing a game. Not doing themselves any favors trying to develop in silos and cram it back together down the road.
In fairness, every game goes through modules though. They are the tech demos that each team produces be it in one studio or multiple. They still stitch them together as it progresses through Alpha. This is for pretty much any game as well. Not just here.
The only difference is that they have given us access to see and play the tech demo/modules. Not sure how many games you have worked on etc but your whole principle that they would work in serial and parallel is wrong in terms of game mechanics, tech and requiring stitching. Not to mention they would need to rework it more than now.
You see you would get a cycle that every time you bolt the next part on then they would have to reiterate what they have done already.
By having teams work in modular they can all build to spec and import together. There is already massive cross over between teams and you can see that from when blockers occur and teams are pulled in and similar. That is literally part of games development 101.
Edit:
We've been doing multi-studio development a lot longer than CIG...we run continuous integration and do everything we can do minimise barriers between teams. It may appear to be easier to manage at first if you give each studio full autonomy and let them just get on with it....but it comes back to kick you in the ass.
Don't expect CIG to ever meet a deadline if they continue with this siloed approach, that's all
Reading this makes me wonder what you do because you seem to be missing that they are working of course modular but they still work with integration because they are required too for the tech to actually communicate.
And you clearly don't understand the schedule report either if you ever think they will hit the end date total since each module is their target date and the schedule just shows the end date to the last module expected to be complete. The hasn't stopped them from hitting specific target dates to specific modules.
Also when you say they are building modular, of course they are to a point. That doesn't stop them from testing internally integration as new tech comes. In fact take the FX teams that are all working on different stages, different games even and yet they are still integrating the tech/tools between it in their live 3.0 build which by the way they have had for at least 2 months integrated and working through because the press has played that integrated 3.0. Add to that the fact other teams are stating and showing they are using the same tools and integration to 3.0 shows they have a fully integrated build. It just so happens 3.0 is the first build of this.
With that it means as new things on the schedule are being complete they are bolted into 3.0 and tested again. That is clearly how an Alpha build would be produced. Actually it is more pre-Alpha but I have explained why calling anything pre-alpha is hard work for marketing.
The fact they are still implementing the tech in engine and making significant changes to said tech is to show they are in pre-alpha though and that you always start in modular tech builds. You stitch them together during you Alpha process and then you re-iterate on that because then you can replace the small modules in the build as QA and similar work through them.
So 3.0 is their first integrated build. That is why we have seen what we have for a few years. If you miss understood that we was later down the development and so expecting it to be different than fair enough but I think you have very much misunderstood where they are relative in their development schedule overall and I do think it is down to CIG miss communicating this and using what would be considered as incorrect development stages due to marketing requirements as people buying into a Pre-Alpha right up to 3.0 Alpha release would be a much harder pill to swallow.
I have probably repeated myself a few times here but I am trying to explain the principles of where we are at.
2.6.X branch is modular because they are tech demos like you would show your publisher initially
3.0 is the first integrated build - this would have been an internal build for over 18 months now where they have all of the 2.6.X modules in it. We just haven't seen 3.0
During that though they have re-introduced current tech and adding new tech. This has allowed certain teams to work on items independantly and then intergrate them as they are ready. We are seeing in the schedule these being complete. Every time a part of what has been complete on schedule since it's public showing those parts will have been in 3.0.
To suggest they are throwing it all together last minute and haven't been integrating it, frankly seems silly.