It's not snake oil, but it's not something revolutionary either. From the paucity of info available from the manufacturer it appears to be a mid/side processor. Read this
article for an understanding of the M/S process. I believe Alan Blumlein described this in the 1930s.
A summary of M/S is that it breaks down a left/right stereo signal into a mono mid channel and 2 side channels. The stereo image size can be increased or decreased by how the side stereo signals are mixed back into the mono mid signal.
The
Manley Backbone is a mastering studio preamp that has built in M/S processing. The Rupert Neve
Field Editor is an outboard M/S processor that offers extensive control in manipulating the stereo width and depth.
Being that M/S processing has been extensively used by mastering engineers for decades and is also readily available as DSP plug-ins in most recording/mixing software, I don't see why high end, audiophile oriented manufacturers would want to incorporate the QOL process into their products.