Well the Horten bros. and Jack Northrop showed some flying wings without a fuse.

If we assume that an airfoil gets its lift from the pressure diferential between the upper and lower surface, then the fuse would only be included if it was shaped like a lifting body. If we use the lower surface at a high alpha, then we might get some 'lift' from it. However most model wing areas are given using the tip to tip wingspan. Interesting isn't it?