A question about the using imposter + hlod

I recently tested on making the hlod with imposters. And got some questions.

My test procedure is following.

  1. Add a imposter actor on the last lod.
  2. Check “Use max load as imposter” for actors.
  3. Create clusters and proxy meshes.

By the way, when creating the proxy mesh,
If all actor in cluster is checked “Use max lod as imposter”, The HLOD not created correctly.
However, if i generate a proxy mesh with clusters containing imposters and some static meshes, The HLOD is created properly.

I saw engine source code. (MeshMergeUtilities.cpp)
When include only imposters, the code didn’t enter to merge the imposters with raw mesh and to generate imposter meterials.

Is there a specific reason for that?
Should i generate a HLOD, including imposters and some static meshes?

Thank you!