S3 Artifacts and the artifacts cache

So, I'm using the S3 artifacts storage for my rather large artifacts and it works well. The agents upload the artifacts and download from them.

However, it doesn't seem to jive with the local Artifacts Cache on the agent.  The agents do download the artifacts from S3, even though they are present in the cache.  Looking in the cahce folders, I see the .json files having entries like:

{"myUrl":"https://teamcity.foo.com/httpAuth/repository/downloadBuild_BuildCore/5576.tcbuildid/teamcity-ivy.xml" ... }
And allo of this ina httpAuth folder.  I am guessing that the cache works as a cache for the regular httpAuth artifacts storage only.

This is a bit of an annoyance.  Since the artifacs are large, are already cached on the agent (having been created threre) but still get fetched from s3 every time, taking unnecessary minutes of transport.

Am I missing anything here?