Jerry - I am not really interested in prolonging the debate either. Personally, I think the burden of proof is on those who think pointing the mike down is better. As is clear, I don't. And, circumstantial and theoretical evidence now provides some support for my view. Even if it makes no difference, pointing it up cannot hurt. So, I will continue to point mine up. Others may do as they choose.
The lower the frequency the less the orientation matters, ...while the higher the frequency the more the orientation counts. Since the Audyssey mic bundled with our AVRs/AVPs was tested and calibrated in an upright position and its corresponding calibration file was burned into the AVR/AVP, IMHO it should obviously be a no-brainer into which direction the mic should face during auto setup. Right?