Parallel syncs do not return Overwrite issues as exceptions.
When a normal sync is run, any writable files in the workspace will
cause P4Exception to be raised for the overwrite issue.
When the same sync is run with parallel arguments, No exceptions
are raised, instead the overwrite reports are spewed to stdout (or stderr),
but they do not generate exceptions.
From internal case 00228015
Recreated internally - this looks like a change in the underlying C++ API
behavior. It may be possible to modify the bridge to compensate.