This is a claim that should be EASILY measurable. Why then are there no such measurements available, by you, or any other user of this cable, or (perhaps most importantly), from the manufacturer?
The manufacturer does/did provide some generic frequency response plots suggesting better low and high frequency response from gear connected to the mains with their cables. No real data though. Most likely because they don't have any.
I'm going to put it to the test. Ordering one this evening.

