The friction referred to is the friction in the main gearbox with all that stuff turning, the residual affect without any power from the engine going into it is for the gearbox to also turn in the same direction the main rotor is turning.
In the B206 the tail rotor might still be turning under power because it's driveshaft comes off the back of the engine reduction gearbox. Hence, right pedal would give you a counter-torque to the drag effect of the main gearbox turning. However, I'd be most surprised if the engine kept running after ET driveshaft failure if it was under load at the time of failure.