I've made this several times since it was published. I puree the sauce at the end to make a nice, thick sauce with the apples and shallots. It gets around the rosemary leaves floating around. When you look at the picture, it looks like that's what they did and that's why i did it that way.
I used unpasteurized apple cider, which probably ended up making the recipe too sweet (and I usually liek sweet with meat). I thought about adding a knob of peeled fresh ginger to spice it up, but I chose to go with the recipe as written (other than using slightly fermented apple cider). Agree with previous reviewer - the stem of rosemary definitely needs to go into a bouquet garni bag - otherwise, it falls apart and the needles remain in the sauce. Won't be making this again.