ivanj, I think that Dick Olsher was repeating Sound Lab's marketing explanation of why their flat panel design is better. If you compare the in-room frequency response graphs of the Sound Lab to the ML Montis, the Montis looks pretty good:
http://www.stereophile.com/content/martinlogan-montis-loudspeaker-measurements#dcpcdPYl2Q74hhzt.97
I'm not saying that the distortion you refer to isn't real, I just don't think it's a major factor in the speaker's sound quality.