I'm finding this discussion belatedly. Unfortunately. It sounds fascinating.
It's interesting to me that you thought of that one story as a first time--while it was the first time I've wrote a relatively explicit slash, I certainly didn't see it as a first time in my own head. I did implicitly assume a previous relationship between D/M. Maybe too implicitly. I figured they got all that first time stuff done and swept under the bed years before. Now, the bits with the nautical ties, well, maybe that was a first between them *g*