You will probably shoot me down on this but I have a theory as to why you W may want some stake in the property....it's you handing some trust over to her by handing a portion of that property to her in paper. It's you showing some faith in the two of you two, symbolically...to me anyway.
I guess in a way I can actually see how you deeding a portion (or whatever it is she wishes) over to her as truly putting a stake in your marriage and sharing with her. As attached as you are to the property (and I do understand that) it's as if you would be saying.....I'm here for the duration and I'm willing to share everything that's important to me....with you. I'm not sure I buy the vengeance thing (even if that's what she said)....but I can certainly see how if you were to give on this it would ease the anger on her part regardless....once again, it's a trust thing.
That's just my observation on this one though. Once again I feel you'll probably shoot me down on it.