With all the joinery completed on the legs, I could work on rounding over their edges. I went slowly, raising the 1/2" radius bit a little each time around the circuit of all 4 legs. I stop/started short of the two stand-offs - the raggedness there will need to be blended-in by hand later. I continued raising the bit until there was no flat spot left on the edges.
Surprisingly (to me), I was able to radius the tips without any tear-out.
With the edges rounded, I could see how much further I needed to cut-in for the narrowed stand-offs.
I chucked-in the core box bit again, set the fence, and then kept nibbling away at the excess. Again, I took my time, raising the bit a little each iteration and checking the result. I kept going until the concave radius from core box bit aligned with the convex curve of the edge. The arrows below show the inflection point.
With a round file and some rough sanding I'll be able to blend-in the transition just fine. And we all love sanding, right?
Splinter - the dowel centers are a good thought if I can keep them from scratching the wood while positioning the legs. I'm not sure how much flex they'll have once the stretchers are glued-in. Unfortunately, I don't have any dowel centers to try that method.
Rob - Now Sam was a real craftsman. I envy the guys who can say they attended one of his classes.