From Doc:
Mapping FVF to DirectX 9.0 Decl
D3DFVF_XYZRHW -> D3DDECLTYPE_FLOAT4 /D3DDECLUSAGE_POSITIONT / 0
D3DDECLUSAGE_POSITIONT
Vertex data contains transformed position data. (D3DDECLUSAGE_POSITIONT with UsageIndex = 0) specifies transformed position. When a declaration containing this is set, the pipeline does not perform vertex processing.