So I've spent some time think about alliance charters. They seem to be around a lot, and are generally considered vital to what people consider "an alliance." Yet at the same time they rarely seem to make much headway in the world and for the most part we don't really think of them.
Ultimately, they seem to be a strange document. They are considered to define an alliance. They determine if it is democratic. They determine who makes decisions. In some cases, they are used to define who else should be regarded as an alliance (GOONS is a good example of this). For some, such as the LSF, they are pivotal in defining the character of the alliance in the way that they dictate decisions be made.
And yet, at the same time, they do surprisingly little. If you have an MDP with another alliance, the fact that they change their charter does not change the status of the MDP. The fact that they have to vote to go to war does not change the fact you will regard them as being in breach if they do not follow you to war. The inner workings of an alliance are not of relevance when you go and demand compensation for the fact that a member has just attacked you.
I do not think that a charter and the alliance are the same thing. You can change a charter and the alliance remains. If IRON were to become a democracy tomorrow, it would not change the fact that it is still IRON and is a continuous entity that existed yesterday.
Ultimately, I think the charter has nothing to do with the alliance. I think it is a contract between members as to how they will act. It is not their contract with the alliance as an abstract and the alliance is not tied to it. It does have an impact on how the alliance acts, but only because it controls the members and they control the alliance. It does not directly control the alliance.
That said, it is still important to have a good charter. By good I do not mean it must have a certain form of decision making or rights and duties. It must however be clear and unambiguous. It should make it clear how decisions are made. But most importantly, it should make it clear how items which are not in the charter are decided and dealt with, as ultimately this is also part of the member compact that exists in every alliance.