Each of the throughlines in a story can be seen as standing alone or as standing with the other throughlines. When selecting which Classes to assign the throughlines of your story, it is extremely important to remember two relationships in particular among the throughlines:

The Overall Story and Subjective Story throughlines are always a dynamic pair.

And....

The Main Character and Impact Character throughlines are always a dynamic pair.

These relationships reflect the kind of impact these throughlines have on each other in every story. The Main and Impact Characters face off throughout the story until one of them Changes (signaled by the Main Character Resolve). Their relationship in the Subjective Story will help precipitate either Success or Failure in the Overall Story (suggested by the Story Outcome).

What these relationships mean to the process of building the Throughlines in your story is that whenever you set up one Throughline, you also set up its dynamic pair.

For example, matching the Main Character throughline with the Situation class not only creates a Main Character Throughline of Situation in your story, it also creates an Impact Character Throughline of Fixed Attitude. Since Fixed Attitude is the dynamic pair to Situation in the Dramatica structure, matching one throughline to one of the Classes automatically puts the other throughline on the opposite Class to support the two throughlines' dynamic pair relationship.

Matching the Overall Story throughline with Manipulation to create an Overall Story Throughline of Manipulation automatically creates a Subjective Story Throughline of Activity at the same time. The reasoning is the same here as it was for the Main and Impact Character throughlines. No matter which Class you match with one of the throughlines on the Dramatica structure, the dynamic pair of that class matches the dynamic pair of that throughline.