Hi'ya
An't analyst folks great

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We're only a little shop, so folks get to be Analyst, Designer and Implementor (Code typists, wot).
As a project proceeds through these loose phases, it would be good to be able to introduce 'the how' into the model.
I'm at a bit of a loss as to why you would strive to keep a model simple, thats not the same as providing a simple view.
My soul screams for 'Action Complete' models, there are lots of productivity benefits, to be gained; consistancy, completeness, one representation, all aid maintaining software systems.

Could we introduce a property on a operation that pointed to an activity diagram... some kinda addin to provide a context menu option.
I'm thinking then that, you would be able to execute the model before producing the implimentation.
Stay tough
Kevin