Sound travels through structure as readily as through air. Every screw that passes through a board into a stud is a short, stiff bridge: it transmits vibration from the face the sound hits to the frame behind it, and from the frame into the far face. A wall held together entirely by screws behaves acoustically worse than the same build-up with a flexible connection.
The system uses a profile that accepts the board edge and holds it without clamping: the board sits in the groove, the H-shaped EPDM seal closes the line, and no fastener crosses the acoustic layer. On the 10 or 12 mm non-combustible board this is done without damage to the board face, which also means the board keeps its full density at the edge — the place where leaks start.
There is a second benefit, and on fit-out projects it is often the one that decides the specification: reversibility. A clipped board can be lifted out and put back. Services that were built into the wall can be reached without demolishing the finish; a wall can be reconfigured when the tenant changes the floor plate. Screwed and taped walls cannot do this.
The cost argument usually comes up here. Clipping is faster per square metre than screwing and filling, so the labour saving pays for the profile. What it does not pay for is the discipline: the boards must be cut square and the studs must be set out accurately, because a clip has less tolerance than a screw. That tolerance is a design responsibility, not a site one.