You've read it right-these potatoes are smashed, not mashed-which means that there should be some lumps left. Both the lumps and potato skins add robust texture, which you don't get with regular mashed potatoes. If you don't have a potato masher on hand, using a large fork will do the trick.
If you want to trim a few calories during the holidays, use fat-free half-and-half in this recipe instead of regular half-and-half. No one will guess because the potatoes will still be rich and tasty.