If vertex clustering is used as the simplification algorithm, there's no need for the geomorphing buffer and seamless LOD morphs can be done entirely in-shader.
A number of commercial game engines use similar techniques.
The advantage of using geomorph buffers is that higher quality simplification algorithms can be used for greater quality and efficiency. A pure vertex clustering approach is simpler and allows for smaller data, which may be better for streaming i/o.
If vertex clustering is used as the simplification algorithm, there's no need for the geomorphing buffer and seamless LOD morphs can be done entirely in-shader.
Video showing LOD-morphing here: https://youtu.be/akOk2wAb0yo
A number of commercial game engines use similar techniques.
The advantage of using geomorph buffers is that higher quality simplification algorithms can be used for greater quality and efficiency. A pure vertex clustering approach is simpler and allows for smaller data, which may be better for streaming i/o.