The AGUSTA 139 requires a significant difference in force to rotate the rotor in the direction of rotation as opposed to rotating in the opposite direction. I believe this is caused by back pressure in the hydraulic system.
I would say that where you turn the tail rotor can make a difference. Again in the case of the 139 you are turning the blades with a long lever arm, no centrifugal force to hold the blades in position and driving through the elastomeric bearings.
Practicaly we all turn rotors by hand and gently does it is the way forward.
However being aware of any cautions in the flight/maintence manuals in relation to rotor systems is important e.g the R22 caution not to pull down main rotor blades.
How often do you see aircraft main blades tied down so tightly as to be outside the manufacturers recommendations.