Like doing your income taxes yourself, sometimes Loudspeaker testing can get too involved for even a 40 year Audio veteran. No matter how hard you try and how careful you are, free field measurements on a test range can never be as accurate as those taken in an actual anechoic chamber. And single channel measurements can never match 20 channel measurements.
NWAA Labs is in the famous Lockheed Martin "Skunk Works" building in Santa Clarita. The Chamber was built in the late 1940's by the Engineers that were testing cutting edge Jet engines. When you walk into the chamber, you can "feel" the quiet. There will be NO artifact of any kind in the test data.
Is this the real world?...No... But to predict your Pro Loudspeakers IN the real world, you need to know exactly what your loudspeaker will DO in the real world. The chamber is the place to find out.