mitchellh/vagrant — pull request #4653 by sethvargo (2014-10-17 15:24:31+00:00)
Title: VMWare does not support --parallel

I am not sure if this is a bug or just undocumented, but neither VMWare Fusion or VMWare workstation support the `--parallel` flag. We have received a few support tickets around this /cc @mitchellh.