Mojo - if one close mics a driver in ANY ported system, one will see a sharp rolloff from about 1/3 octave above the tuning point. At the tuning point, the woofer is barely moving, and most of the output is from the port. If one has the mic 0.5 inch from the driver, it is several inches from the port, and the resulting measurement will be what S&V got in that test.

From a look at the response curve, I would guess the tuning point of the EP125 is about 38 Hz.