That is exactly what I thought.
Interestingly, looking at the charts at the website Alan listed, the update from v1 (2000 measurements) to v2 (2005 measurements) on the M80 shows improvements in frequency response across the board, but particularly in the mid frequencyes 100hz - 5kHz, improvements in off axis response, and a reduction in THD + N in the mid frequencies.
Now that I have a better understanding of what those charts represent, I can conclude that the poster on the other forum was blowing (technical) smoke out his woofer port.
