1. I don't agree with always agree. (There's irony) Always validate.
2. Pinhead: It's a matter of triage. The attraction is the last thing to come back. First, you stop the bleeding. The WAW needs to feel safe to express her feelings. She needs to feel that the changes you are making are real and not just to get her back. She needs to have fun around you and not feel badly for you or find you a drag. But it's not a linear thing. In the same way that the littlest setback can bring the panic and anxiety back in you, the littlest sign of reconnection can bring back her panic and anxiety and she can withdraw. Remember, a WAW walks away because she has come to an emotional state where it is less painful to walk away than to face the problems in her relationship. Someone (possibly coach?) compared the process to befriending a stray cat. I think that's about right. On the one hand they want to reconnect. On the other, they're afraid.
Finally, the books and the DB coaches will tell you to STALL any move towards separation or divorce. However, I have not been doing research into sitchs where there is a PA or EA and don't have experience there (I don't believe so, anyway.) I don't know if the stalling tactic applies in those cases.