Assessment of building regulations

I read it as if construction was done at the front according to the development plan and [Grundstück]. no hinterland development would be possible afterwards?
If that is true, you are applying for an exception to the development plan. This can, but does not have to be approved. And then it is also possible to allow this exception with conditions.
Please correct me if I have failed in understanding the text.

That is nonsense. Development plans (including the text part and justifications) and design statutes are discussed in public meetings and are administrative acts that must comply with formal requirements. There are no secret additional protocols that one can only learn about by whispering.

However, a hinterland development outside the actual building window is desired here. According to the development plan, nothing could be built there.

"Predecessor threads"

Thank you very much for the links. That saves a lot of effort and you can see right away that basically everything on the topic has already been said.

There are no secret additional protocols that can only be learned through whispering.

The additional protocols are not secret and I remember the rules for whispering differently. Basically, I consider the approach of formulating stipulation-like requirements for exceptions and exemptions instead of creating a new development plan questionable. However, perhaps this is the fastest way to achieve the urban planning goal of densification despite an opposing legally valid development plan.

We received remarks from planners of the general contractors we have spoken to so far that the requirements are not coherent and contestable.

Legal steps that could even be promising here will probably only be financially and temporally feasible for a developer who does not mind starting the project only in five years.

How would you assess the requirements?

Considering the information from your other threads, it will be much easier to comply with the requirements than to legally challenge them. The 30cm knee wall and the desire for a cross gable versus dormer seem ridiculous compared to the alternative of starting a dispute with the approval authority.

sounds to me like a loophole

That sounds like you did not understand the statement. It is not about the dormer width, but about the setback to the exterior wall of the ground floor.

The 2/3 rule apparently does not apply; how a full floor is calculated instead, she did not tell me.

Your designer must know which version of the state building code is to be used for determining the full floors.

I would comply with the requirements or not do it at all. We also wanted a higher knee wall on our property, meaning no sloping ceilings in the upper floor. The responsible officer quite bluntly told us that we could sue if we have 5 years to do so...

This is now the 3rd post about the same problem. Maybe you could be a bit more precise about what you are planning. What is the height structure of your desired house? How high is the floor slab? How high is it above the ground? Is it possible to sink it further? What room heights / story heights are planned? How big are dormers / cross gables or similar? Can the knee wall be higher if the roof extensions are omitted? Exact floor plans and wishes, where are the problems, plot, budget, neighbors, name of the dog - simply everything. Then solutions can also be sought. Constantly rowing against the building authority won’t get you any further. You have to build according to the development plan, not against it.

The whole thing makes me a bit angry as a third party reading it. The fact is: According to the development plan, you are not allowed to build there at all. The fact is: The office accommodates the prospective builder with an uncomplicated exception regulation, no new development plan, nothing. In return, the office demands restrictions on the way of building, fully aware that otherwise lawsuits from the neighborhood are to be expected, which you would lose, because as I said, according to the development plan, zero nada niente would be possible. Instead of thanking the office and planning as intended, the prospective builder makes a fuss. Give a little finger, and he takes the whole hand. I have no understanding for such behavior. Karsten