Used those. Did not obtain satisfactory results. That's why I was here asking the question I asked.
ThruPaint works fine for some applications, but not all of them, and SketchUV has always been a nightmare to use. I admit I haven't tried Wrapr, bu then $.
I guess what I should have asked was not so much about surfaces as about projecting to individual polygons, by those polygon's normals.
As far as the blending of textures, it's possible, and it's been done, in TW Render's terrain tools. Unfortunately, that is only for top down elevation change applications with terrain / vegetation / ground cover.
There's nothing else quite like 3d modeling and rendering to humble a person, just when they start feeling like they understand things