AntEater,
"There has to be an "aggressiv-kämpferische Grundhaltung" (aggressive basic attitude), in regards to how the association/party tries to attain its goals."
And that is not the case with Scientology?! Of course it is. They are actively engaged in infiltrating economy at leadershiplevels, political structures at decison-making level, public education sector at teaching level. If that is not aggressiveness, than I do not understand what the term means (ad greddi, if my latin is not totally failing: "an etwas herantreten, sich auf etwas zubewegen"). Agressiveness is more than just physical violence (which they also practice in that meant when they limit the freedom of movement of members, and keep them in enforced isolation).
"Especially since every failed ban makes that weapon more blunt. "
That is a risk indeed. But why is not to use the weapon in an effort any better? trying it after good preparation is a chance. not trying at all leaves you chanceless and defeated.
the NPD case did not fall for weak arguments and evidence, but for technical reasons - exclusively. I agree though that the case needs good preparartion. that may be the reason why the interior ministers said they have ordered the Verfassungsschutz to collect further evidence until autumn next year. However, they already seem to have enbiugh material to make a unified public statement like they did, and also in the past there has been enough material to convince several courts in Germany and europe as well to decide agaimst scientology in many cases on basis of criminal laws, economical laws, and institutional laws, and also decide against Scientology's request to be considered as a religious community. If the informational basis and staus of evidence would have been so weak in all these cases, these colurt ruling hardly would have been possible. So: "some more courage, comrades"!
The problem I see is another one: the Eu interfering on behalf of Scientology, since Scientology was able to secure some support on it's status in recent years by massive lobby work at the EU, and winning a courtcase at the EU court. I know that nations today often vilate their own conszoitutions in taking over EU demands unconditionally and pressing them through parliaments unchecked and undebated, but that is no legal argument why not to rsist such pressures from the EU, but also illustrates the failure of national governments. If in 12 or 18 months the German government still will have the will to accept confrontation with the EU - that is they question mark that I see looming at the horizon. tradtionally germany defends it's interests at the EU very hesitently and passively, where others are pressing for these far more aggressively. A strategical deficit of the Germans that really could ruin this case.
Concerning what you said aboiut the importance of the costitution in lawmaking and and courts:
Article 31 GGFederal law overrides Land law.
Article 28 - 1. The constitutional order in the Laender must conform to the principles of republican, democratic, and social government based on the rule of law, within the meaning of this Basic Law. (...)
- 3. The Federation guarantees that the constitutional order of the Laender conforms to the basic rights and to the provisions of paragraphs (1) and (2).
You say that usually the constitution does not play a role in courts, in the meaning of precedences and specialised (but nevertheless sub-ordinated!) laws from the Strafgesetz, for example, are given more attentiuon. But maybe that is just a bad habit!? The constitution is very clear about federal laws needing to obey the constitution, and federal law braking Länder law, and Länder constitutions are needing to obey the Grundgesetz. So, the constitution does not say that it must be accepted that a court proceeding violating basic principles of the federal constitution - is intended, or must be tolerated. In other words: if proceedings distance themselves too far from the constitution - who say that in that case you cannot prerss much harder to come to that ground of the constitution again? In more lush language: pea counting may be nice and fine, but it surely does not set the constitgution out of effect - you can push for the constitution being seen as the basis for any specilaised laws being used. Eventually (and in this case: ironically) you can even go to the EU court and can file a case against Germany if a german court refuses to accept the dominance of german's constititution over specialised laws, since that would mean the the above quoted articles of the constitution are not followed. -This information is not my personal assessement, but the assessement by a lawyer for Verwaltungs- und Staatsrecht whom I occasionally deal with, since his brother, our house lawyer, and me are loose friends, and in very different contexts we talked aboiut these things: the meaning of the constitution and in how far it is the basis at courts, and can be sued for at international courts.
Probably there is possible counterargument, but that is to be expected. If there would not be differing interpretations, we would not need neither lawyer nor attorneys - only judges.
In any way, we have far too many laws and "Verwaltungsvorschriften" in gemrany, and in the West in general. "cut the sh!t by at least three quarters", the same man once said.

- What should I say? Agreed!