Cadet and Lost18 are right: It doesn't matter. Unless you know you don't want the M, then leave your options open. As I just wrote on my thread (sitch 7 months in), I stopeed even wondering if I want to save the M or not because it doesn't change my actions. What I do in DB is what I should be doing anyway, to spare myself a lot of trouble, to protect my dignity and my self-respect.
As for the MBR, the purpose is not only to restore your sanity, it is also to gain her respect. Perhaps it will be clearer if the roles are reversed. Imagine you have an A, your W knows about it and yet she still tries to placate you and avoid rocking the boat, letting you stay in the marital bed for instance. Now imagine the opposite: she calmly tells you: "I don't want to lose you, but I will have none of that. You leave the marital bed as long as this lasts." Which one of the two do you respect and love?
Another thing that I repeat a lot to newcomers: it ain't over til it's over. And even then, it isn't over. Don't think that because you're headed to dissolution, your M is over. Don't you think that people who saved their M just before signing their D papers also thought that it was over at your stage? And people even get back together and remarry after D, which can be a good cleaning treatment for a relationship. If it isn't clear to you yet, read more of the success stories at the top of my thread. For instance, T0324 just had her D proceedings completely canceled yesterday. Her sitch lasted 16 months and was a sure D in her mind at some point.
So stop obsessing about what will be or not. You just don't know. You don't. Do the right thing and leave your options open.
M39 D6 D3 (at S) S 2014-09 D 2016-09
"You can't start a fire sitting around, crying over a broken heart" - Bruce Springsteen.