As you may know, guvnor is a set of components that can be used separately, so for example if you want to model business process you can pick the process designer embeded it in your application and then find a way to generate the rules based on a metaphor that suits your business analysts needs. You will find that this is a very incremental approach when you need to decide how much control you will give the analysts during the first phases of your adoption. Usually you will see that during the initial period of adoption your analysts can only see the rules that are being executed, then you can provide a way to parameterize them and finaly you can give them an authoring tool.
Hope this helps.
Cheers