Phase Inversion on CJ equipment

The manual for my CJ pre-amp has warnings periodically saying that the pre-amp is not phase-inverting. This means that I have to send the red output on my amp to the black input on the speaker in order to get the driver to go the right way. They say that they do this for purity reasons, to avoid any added distortion. Why don't other manufacturers do this if its so great? Also, does anyone know what this is doing to my amplifier now that I've mix-matched the hot lead?