Right, I think "GAL" and "180" are different ways of saying the same thing -- this is just giving you another perspective on how and why.
The book says the other person is moving away from you. If you pursue they move away farther. This moving away is not physical, it's emotional. The farther they emotionally move away, the longer it is to come back. Therefore, the first goal is to limit how far away they move, by moving in the opposite direction and pulling back yourself! That will in theory not give them incentive to move away any farther and stay where they are.
Then, you need to give them incentive to move back closer to you. You can't provide that incentive by being an open book or by being predictable, they already know that story. You have to show them a story they don't know, and make them want to learn more.
Therefore, if you "180", they will start to think "who is this person, this is not who I thought I knew". That's why it's so important to be *consistent* with your 180's and not backslide. If you give them even a glimpse of what used to be, the intriguing part evaporates. Same thing with GAL -- where is this guy going and what is he doing? Why does he seem to be having fun without me? He should be miserable, but he isn't, why not?
Those are the questions that start to tease the person back to the table. If they ask questions and you explain all your plans and motivations -- no mystery left. Therefore, you need to be polite and supportive, but at the same time private and aloof. The most important thing is to project confidence and comfort ("act as if" from DB).
People are attracted by confidence, and repelled by a lack thereof.
All of this is counter-intuitive, and goes against your instincts. That's why it's so HARD.
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015