This is a GREAT idea for furthering your understanding of Dramatica. I'll do my best to help as I have a pretty good grasp of it, having taken Jim's mentorship program. But don't be afraid to question my assertions either -- a year ago I'd never even heard of Dramatica!
I hope you don't mind I'll try the approach of asking you questions instead of just stating stuff, as I found that really helped me when Jim did that. (despite how it puts you on the spot, but Jim never threw any cymbals, drums, or Mack trucks at me )
First of all, when figuring out the MC Throughline, the Do-er vs. Be-er question definitely needs to be considered first. Even if you think you feel a lot of Innermost Desires, if he's obviously a Do-er when it comes to his personal issues, then he's going to be in Situation or Activity. And when you see an MC doing something physical that is obviously conflict-related (drumming until your hands bleed!), if it seems to be related to his personal issues, that makes the Do-er nature pretty clear. ESPECIALLY if he keeps doing it (showing that it's the "preferred" approach).
When you talk about his belief that he could be one of the greats, you may have been seeing his Issue of Fact (belief in something real; it's a fact that he's talented), combined with his drive to prove that talent (Unproven), rather than all of his personal issues stemming from a Fixed Attitude. You can try the old litmus test: If you removed his belief that he's one of the greats, would he still have any personal problems?
Oh, you also might have been sensing the IC Benchmark of Innermost Desires, something like being able to measure Terrence's influence by how much he ruins his students' (esp. Andrew's) deepest desires and dreams. Preconditions might have been part of what you sensed, too; perhaps giving up his girlfriend was his own (somewhat silly) precondition that he met.
(EDIT: Remember also that a Concern of Innermost Desires is the stuff of unfulfilled longings, unrequited love, deep yearnings, subconscious desires and dread ... it's not quite the same as the conscious determination and drive that you see in Andrew.)
To be honest, while watching the movie I thought the MC throughline might be Activity. Until the last scene, when the two of them almost merged over that incredible performance -- that screamed an RS of Activity.
Hmm. I'm trying to think how I can help here, because I think I sort of jumped several steps, kind of got the IC Domain/Concern (esp. Impulsive Responses) by feeling. Jim's mentorship is really good for developing the feeling of Domains and especially Concerns.
What might help is to remember that the IC Throughline is not so much about a person, but a force of influence, which is usually represented by person(s). Although the IC Story Points can often be attributed to the character, their most important feature is to cause influence and conflict in others (always the MC, but often other characters too). Despite its deprecation, I think the word impact is still useful here.
So ask yourself: where was the conflict that other people felt from Terrence coming from, and what area was it in?
What made it easier for me to identify the other throughlines was a strong guess at the OS Domain (and Concern, because of being pretty sure on top-right). Even though I didn't have a good handle on exactly what the OS was, a great trick is to identify some characters who are important enough to show some conflict, but aren't the MC or IC. Now, it's possible those characters don't have a role in the OS (they might just be helping to show the MC issues or IC influence), but if they have enough screen time they probably will have an OS role.
For Whiplash, I picked girlfriend Nicole and Andrew's dad:
- What happens when Andrew first asks Nicole on a date, what is her initial response?
- In the scene where the dad and the woman lawyer (I think she was a lawyer) talk to Andrew, what is happening, what are they trying to do and where is the conflict coming from?
- There is conflict between Andrew and his dad around a food item, what area is that conflict in?