The transactional process, is the process of which elements are interdependent. Meaning no matter who is in a conversation, if a person leaves or joins the subject in which you are talking about, the subject will always change.
Ex. In the sitcom Charmed, an axe man attacked and Piper thought she would go to the book of shadows to identify him. While upstairs and conversing with her sisters, her grandmother then found a picture of him in a book of fairytales. Then the whole subject in which they were talking changed when the grandmother proceeded to talk about fairytales instead of the axe man.
Some messages are doubtful to some degree. When the same idea is expressed to two different people, they could each interpret it in totally different ways, meaning the message is ambiguous.
Ex. Phoebe told Piper who was upstairs she was going out, she then told Paige, who was down stairs. Piper then thought Phoebe would only be going out to run errands, when Paige thought Phoebe was going to meet her boyfriend.
The difference is very clear. You can say a simple thing, but very simply two people can get two totally different meanings.
When two people respond to each other with the same behavior it is considered a symmetrical relationship.
Now when two people respond to each other with opposite behavior it is considered a complementary relationship.
Ex. Phoebe and Cole are a very symmetrical couple because they share things as one. Cole was cooking dinner and Phoebe was right there to help. When Phoebe set the dinning room table with candle light, Cole went to turn on the romantic music.
On the other hand Piper and Leo have a very complementary relationship. Piper was worried about Wyatt their little boy, and told Leo to go and talk to the elders to see which demon was after Wyatt.
People argue not because of a decision, which refers to content, but because they weren't considered when the other person made the decision...