Cooked the duck breast tonight. Scored the skin/fat, making sure one set of scores coincides with how the piece will be sliced. Cooked in a pan, skin down, on med-low heat, until skin is browned and crisp, meat is about 120 F by then (the fat is a good insulator). Then crank heat to high and flip, give the meat side a kiss of about a minute, just long enough so it looks cooked.
The gastrique sauce looks like lumpy poo in a photo (next time, process it smooth enough for a squeeze bottle) so no pics, but it was good.