Thanks NYC for your reply. You are right, there is no trying. It's a leap off the edge and you're all in or not. We are all in. It was just my gentleness of words in using the less definite word of "try".
As far as openness, I am referring both emotionally and sexually. As has been said by others, it can be easier with the clean slate of a new relationship to forge new ground relationally (both emotionally and sexually) that has not been tread before. I think this is happening with my wife. It would be more difficult to break the patterns of relating with an existing relationship. Perhaps she is trying on new ways of relating emotionally and sexually that she has not been willing or able to try on with me before. It suits her! I always knew she had it in her to be how she is with him, but for whatever reasons it only came out in glimpses with me. Perhaps these glimpses will start becoming more frequent and lasting longer with me as she taps into who she is becoming more and more. If it takes another guy to bring this out in her, then so be it...