>> Your foursome analogy does not work since there is no top, bottom, or progression in this dance. If there is a top, as in music, this means only that of the four dancers only two have the music to their right shoulder, and two to ther left, at the same time, this is also true of the bottom of the room.
Yes, I was only comparing it with The Shepherd's Crook in that it's mainly seen as a demonstration dance (especially as it needs a some knowledge of highland steps) but it does pop up on a social dance programme now and again.
(And there's no progression in The Shepherd's Crook either as far as I'm aware. I wouldn't say there's a top and a bottom to it either - just a "front" and a "back" - top and bottom would refer to the hall, surely?)