Well, an update. I was tempted to just go back to the Arione R3 and try to make it work. Then I started reading about SMP saddles and discovered Steve Hogg's bikefitting website. What a wealth of information. He seems to be well respected. After much hand wringing, reading, and discussion with my LBS fitter/owner (who originally set me up), I decided to test the SMP Dynamic saddle. I rode it 25 miles this morning and the difference was huge. Minor discomfort at the end of the ride which I attribute to my butt being a bit "tuned up" after the last 3 uncomfortable rides. It's a very unusual design but seems to have quite a following. The shape of the saddle made it easy for me to settle into a comfortable pelvis forward position, both in the drops and on the hoods. My 50 miler this Sunday will be more telling, but this "might" be the one. If not, I'll probably go back to the R3 and try to sort it. More will be revealed.