twitter/scalding — pull request #1022 by johnynek (2014-08-15 23:38:25+00:00)
Title: Fix the issue with Execution zip on Merge assuming zip parallelism

The (possibly needless) optimization of toIteratorExecution and forceToDiskExecution on MergedPipe assumed that zip merged into one flow, which was removed due to the Cascading issue regarding uniquely named pipes.