Hello,
The effect of wall mounting to improve the sound is in principal very similar to any non-rear-ported speaker enclosure. On a solid wall they’ll sound stronger than on a stud wall or on brackets.
Similar thinking to placing a rear-ported speaker on a nice solid stand.
The writing from B&O on the topic does suggest something magical will happen, but it’s just good sense to use a solid foundation on which to position the speakers.
Get the tweeters at ear level and you’ll achieve a lovely stereo image. Hang them higher and you’ll get a more bass-heavy and floaty effect, depending on the amount of soft furnishings or reflective surfaces in your listening room.
Julian