Some of the foreigners over here had issues with the split duty trips. The company position was that _total hours_ on duty were within limits and not prohibited by regulations.
Looking in the ops manual, there are no stipulations about split duty scheduling. Scheduling has rules, based on whims of upper management, that facilitate high flight time.
As to fatigue: push pilots near their limits, where QAR reports start to increase, then punish vigirously to cap the errors. Except people are people. Maoists don't understand that, so there will be more QAR busts and bent metal eventually...