"...contracting parties certainly love rules and the predictability that follows from them. After all, legal contracts - including the GPL - state the responsibilities of the agreeing parties for the main purpose of protecting their freedom."
The interesting distinction between the GPL and some of the legally binding (potentially) rules that you are proposing is that the GPL adds to the cliets freedom whereas your rules do the exact opposite.
A major challenge (maybe *the* major challenge) that any OpenACS-based businesses face is that of attracting new clients, to a large extent this usually involves convincing them of the merits of open source. Now, a client that doesn't believe in Open Source, and doesn't believe in sharing source code and/or ideas with the community, is very unlikely to enter into any such contract that you are proposing. On the other hand, clients who do belive in those ideas, or can be convinced by us that they are beneficial to them, will follow recommendations that we give them without any need for legal enforcement. So either way, legality in this area achieves nothing, whereas selling people on the benefits of open source along with sound recommendations can achieve a lot. We don't want to be in a situation where clients are obliged to comply with open source behaviour. Instead they must participate out of their own free will because they realize that this is beneficial to them. Think of examples such as MIT, Heidelberg, and Greenpeace and you must realize that this is true.
