oldster,

"why would Dan Bailey and Scientific Angler go to the trouble to make the fly appear to be floating as it shows unless they, and a large number of well known fly tyers and fly fisherman believed that it should?"

Perhaps because the Royal Wulff is such an iconic fly pattern, is just good looking (to fly fishers and apparently fish too), the photo represents what a dry fly should look like on the water surface, and the reflection is just so artistic. All in all, the photo draws you in and, at least to me, that fly represents an era and an important individual (Lee Wulff) in fly fishing history.