This is closed out as by design because the shader complexity view was previously bugged. Foliage was using depth pixel offset which was not supported in the debug view. This was fixed with CL-2947374. It is also worth noting that shader complexity adds the cost to clipped pixels, creating costly contours around the leaves.
Masked Materials have become more expensive in 4.13 and internal builds than in 4.12.
Images attached for demonstration along with test map using the bush prop from starter content.
Tested with builds:
4.13 Preview 2 CL-3088355
4.14 Dev-Main CL-3092283
1. Created or use an existing masked material applied to a static mesh
2. Use the foliage tool to paint some around the level or place them manually
3. Switch to the Shader Complexity view mode
Results: Shader Complexity view shows masked materials as more expensive than in previous versions
Expected: Shader Complexity for masked materials should not be as expensive
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-34873 in the post.