Say my company is going to build a complicated asp.net web form education system. One of the module is web based registration. To make it flexiable, we decide to use user control(ascx) with rule-engine (work flow) regulating all business logic behide them. Thus in future,for different clients, we can simply config basic existing rules or adding new rules.(Rules stored in db or XML per client).

Now the question is how to deal with the user controls (ascx)? My opinion is for different client build diffrent user control from scratch. other voice is like reuse existing user controls.