In a recent QnA asking Why do the Position of Throughlines Determine Main Character Growth, Dramatica co-creator Chris Huntley explains why the Main Character Growth story point exists in the first place:
Serious MC personal problems cannot be solved by adopting the MC Solution because the MC is blind to the problem, the solution, and for Change MCs both the problem and the solution. In order to get to the point where a MC has the option to change or remain steadfast, he must grow past the blinders or pressures that prevent him from recognizing both options open to him: the path he has always followed (represented by the MC Symptom and MC Response), and the path not chosen (represented by the MC Problem and MC Solution).
One of the purposes of story is to reveal that process of moving past justifications in order to see what is really going on. This is why stories have Acts and why they often end with a Leap of Faith. That Leap of Faith is the moment when the Main Character can finally see the two different paths: the one always followed, and the one not chosen.
In a simple sense, when the MC and OS are in a horizontal (companion pair) relationship, their perspectives on the inequity at the heart of the story are more similar than not. Since conflict exists in that relative spatial relationship, the MC's personal problems are alike to the bigger issue and the MC grows by learning to step away, step back, or just stop his bad behavior
Many fail to realize that Dramatica is a relativistic model. In other words, it is a model of relationships between things not a cookie-cutter story-by-numbers list of sequences. The relationship between the Overall Story problems and the Main Character's personal problems carries with it a potential for conflict, or inequity. The actual conflict occurs between the Throughlines in the space that cannot be named; it doesn't simply occur in one or the other, or both.
A storyform represents a process and a set of states. The state of the storyform pattern at the beginning of the story is different than at the end, and the comparison of the MC Resolve indicates the relative positions of those to states: Change or Steadfast. The MC Growth represents the process that the MC goes through from the beginning state to the end state.
Both Main Character Resolve and Main Character Growth describe the Main Character's "arc". The Resolve defines the state of the arc, the Growth the process. Did the state change when comparing the end to the beginning? If so then the Resolve Changed. If not, it Remained Steadfast.
How that Resolve develops over time, regardless of Change or Steadfast, is the domain of the Main Character Growth. Did they step back or step away, or did they step forward or step up? If the former then their Growth was Stop, if latter then their Growth was Start.
Dramatica's relativistic model will determine Growth for you if you don't know (and is often what I let it do in my own stories). Simply determine the domain of the Main Character's personal issues and the domain of the larger big-picture Overall Story issues and Dramatica will set the Growth for you.
Likewise if you don't know the domain of the Overall Story Throughline but you do know the Main Character's Growth, then you can set the Main Character's Throughline and the Growth. Dramatica will automatically place the Overall Story Throughline in the proper domain.