ABX testing of speakers isolation devices

There is a recent video by Steve Guttenberg’s friend Mark on speaker isolation devices. In the video, Mark uses informal listening observations and a microphone and software to try to distinguish differences between different isolation devices with inconclusive results. He then resorts to a blind ABX test with an interesting control related to speaker position.

I am interested to hear what you all think.

https://youtu.be/XAOD3aUfIYQ?si=pYs72o9UAl-21LH6

kn