Morkus from Orkus
Well, this goes back to the quote from Donald Davidson in the OP:
If the PC winks at the maiden and softens her heart the PC hasn't done two things (wink, and as a separate thing soften her heart) - that way lies madness because it will quickly lead to near-endless multiplication of the number of events that have occurred (eg you'll have each movement of an eyelash through each point of space as a separate and distinct thing that the PC did).
There is one action but it falls under more than one description. In the context of playing a RPG, which involves generating shared agreement on the descriptions that are true in the fiction, I think the question of who gets to establish which descriptions is quite interesting. And I think that saying the player gets to decide what the PC does isn't a useful way of answering the question.
Eh, no. That's not the same thing at all. This is not the case where the winker is committing several micro-actions that are all connected to form one single larger action. He is engaging in the action of winking. And then after that action(and all of its micro-actions) concludes, there is the result of that action, the softening of her heart. The act of winking concludes before there is a softening of the heart.
In a game, I don't get to declare that I am going to pull out my sword, threaten the prince, have him concede half of his lands to me, go farm those lands, harvest the crops, and then sell them all as a single action.