sbt/sbt — pull request #1620 by eed3si9n (2014-12-08 14:28:43+00:00)
Title: sbt resolves dependencies every compile when using %% with dependencyOverrides

The issue is not caused when % is used instead of %%.

Following is reproducible build.sbt.
https://gist.github.com/tkawachi/125cdcad0b0e014f1f44

ref. https://groups.google.com/d/msg/sbt-dev/cUOCbLVXwEQ/O9lzi0atI_kJ