Negative feelings/thought causing some positive results?

Hi! I am signed up for coach training in April (SO EXCITED!) I just received the materials in the mail and it was literally like Christmas. I have been starting to practice explaining the model to some willing friends who want to be coached. One of my friends, who uses the manual for her boyfriend told me that when she demands, starts arguments and get into “blow up fights” she is actually more likely to receive the changes/results from her boyfriend she is looking for. She says that this pushes him into action and he will smoke less, try harder, and be a better partner afterwards (for a certain period of time). She says each time she does this he changes a little bit. To her credit, her boyfriend has made a LOT of changes over the years and HAS become a better partner to her and follows her “manual” a little bit more closely. Needless to say, they do fight a lot.

My question is. How would you recommend coaching someone who sees “positive” results from these negative thoughts and feelings. In her mind, in order for him to change, she needs to keep doing this because she has evidence that it is working.

Thanks so much!