Nigel and XE
"Tail rotor drive failure does not equal engine failure" is too simple a statement.
In the helicopter I fly - AS365N2 a tail rotor/fenestron drive failure, unless in the hover, is not an enter auto immediately scenario. The large fin is designed to offload the fenestron in the cruise so directional control should be fairly easy to maintain.
The tricky bit is landing as a combination of airspeed and power needs to be found which keeps the a/c from crabbing as it touches down. In the Dauphin's case a wind from the right helps.
Don't expect to land off your 1st approach as this should be used to assess the airspeed/power combination. If it looks wrong go around early.
Once you have got the airspeed/power combination right fly the helicopter like a fixed wing with a threshold speed of the airspeed for zero yaw + 5kts
Once on the ground don't relax and lower the collective or you will find yourself leaving the runway as the yaw will develop very quickly. Keep the collective in the same position you landed with and shut down the engine(s). This removes the yaw and allows you to keep straight with brakes
My company encourages us to practise this and it can be "fun"
HF