I learned to drive in small cars with no power steering. As such, I have a good feel for how much more effort is required to move the steering when stationary, as compared to moving.
The ability to move the power-steering while stationary is useful - it is sometimes necessary when parking in a tight spot, and it is a useful test when evaluating a used vehicle for purchase.
However I think that power-steering while stationary will put extra load and therefore wear on the steering and front tires.
Is it good advice to attempt to avoid power-steering while stationary unless absolutely necessary avoid this extra wear, or is the extra wear so small that it is not worth worrying about?