I feel like this question could be academic if you aren't careful. You can do just about anything that you want with Dramatica by bending the rules. It is malleable enough. But, unless the bending serves your story idea -- there's really no point. It doesn't matter if it is perfectly formed. It doesn't matter if it allows for an Oscar-worthy performance.
If you start with your story idea as the noumenon, then you find a Storyform -- you will end up with a Grand Argument Story (GAS): the phenomenon. Admittedly, you can reframe the Storyform as the noumenon, then find a story -- which leads to a GAS: the phenomenon. All roads lead to Rome.
Regardless of your creative process, Storyform will sometimes fight the phenomenon that you want to create. This is where the Substory comes in to play. The Substory malleates the Storyform to fit your noumenal (ontic) vision.
While the function of a Substory is to malleate the Storyform, the methodology of the Substory is context (vividness). Context is created by additional data. Data can be created by a number of processes: contrast, comparison, manipulation, amplification, etc.
Whereas a Substory's form is malleable, its function is not. Substory function is demanded by and subservient to the needs of the Storyform (which is demanded by and subservient to the needs of your story idea).
Thinking about Substories and Storyforms, an analogy of WordPress themes and plugins popped into my head.
The plugin/Substory does nothing by itself. But that doesn't mean that Substories cannot be powerful a la the butterfly effect. A Substory might justify a single character action or it might completely reframe a story through context:
Caveat Emptor: I merely muse. I make no claims as to the veracity of my statements.