hadoop-tools still suffers from the same sorts of problems though, just on a smaller scale, made worse by how it is laid out vs. the rest of Hadoop. To be more specific, most of the sub-projects do:
share/hadoop/(project) <- hadoop bits
share/hadoop/(project)/lib <- dependencies
tools, on the other hand, just does share/hadoop/tools/lib, with both the hadoop bits and the dependencies intermingled. Every time someone issues a command that needs tools support (e.g., distcp), all of this stuff gets pulled in. This is a historical issue, and probably one that should get broken in 3.x.
If we move all of the metrics sinks so their own universe, the file layout should be changed appropriately.