All the sites recommending low and slow say American ducks are a bit tough and the meat benefits from this treatment. But I can see how it would have floppy skin.

All the sites recommending a temp of 300-350 say it'll crisp up the skin much better and don't address toughness.

I've got a 6lb bird that I'm thinking I'll stuff with orange quarters, garlic, and herbs. I'm going to put it on an extra rack right above a drip tray, skin pricked, rubbed with spices, breast side up. I'm going to set my barrel up for indirect at 300-325 with coal and Cherry wood, with two smaller coal piles one on either side of the duck below and to each side of the drip tray. Cook time 2.5 hours 15 mins rest. Thoughts?