I'm in two minds - sure, they're using warped physics to flog idiots stuff that does nothing, but equally the hifi brigade are daft for believe the rubbish they get peddled!
Over time I've come to believe that the HiFi brigade are no more daft than we "audio professionals" are, though their daftness shows itself in different ways perhaps. Confirmation Bias [among other biases involved in this] can
literally make something sound better to a person, because our perceptions ARE our reality and so that thing you changed
does actually make it sound better. To you. But... If you happen to be in a position to have your opinion be valued by others, Their Confirmation Bias that "Maddox is a pro and he's pretty smart and I bet he knows what he's talking about" will make it
actually sound better to them as well. And then, because several Audio Professionals hear something "Sound Better", the Confirmation Bias teams up with The Bandwagon Effect and suddenly an opinion that was wildly flawed by inherent biases to begin with becomes Established Fact.
And make no mistake, we as Audio Pros are no more immune to Confirmation Bias than any other human. We hear with our Brains, not our ears. And our Brains are MASTERS at lying to us. Of course we don't have much choice but to do our jobs based on what we hear, so in that regard we're a little stuck with our Hearing Brains whether we like it or not.
All that being said, cutting angles into CDs to make them "sound better" is stupid and should be regarded as such...