The technique provides significant additional image stability, especially when the listener is moving or off-axis.
There are several problems involved in mixing with an additional centre front channel for many engineers.
The channel itself was originally designed for dialogue in matrix cinema surround systems and does not have a direct application in music mixing, where a 2-speaker stereo stage is generally, and traditionally, employed.
However, if the CF channel is left silent, consumers may believe there is a fault with the disc or with their equipment.
Not only does CF content now blend with the mix: in addition, the resulting soundstage is more stable and listener-position independent, while the listener can confirm that something is actually emerging from their centre-front loudspeaker.