DAle I made my first one by shaping the riser . Now I do them all like you do. I believe it makes a stronger riser and actually looks more streamlined. Its also a lot easier. All you have to do it cut the ramps for the fades on the back and make sure they are right. When I want a little more deflex for the belly I just add a fairly heavy power lam to the belly and it bends to the shape of the limbs past the fades of the riser. It basically is a riser extension.
God bless, Steve