Let's face it, watching the other pilot pole the aircraft isn't exactly a life threatening job,
If an airline pilot workload is getting right up to his upper limit by watching the other bloke flying,
now there speaks someone with no real understanding of the role of the PM.
While the ace of the base is flying manually, who do you suppose makes all the mode settings for the FD, continuously sets the HDG bug, sets the airspeed bug for every speed change, resets and confirms the altitude selector setting, makes the FMC entries, does the RT, runs the checklists, selects gear and flap, monitors the pressurisation system, addresses master caution alerts, monitors the position and altitude of the aircraft with reference to the departure/arrival, monitors terrain, monitors proximate traffic, talks to the cabin crew and if necessary runs the QRH?
That's what you call a workload.
"watching the other bloke fly"
are you having a laugh?