The scaling of a group has also another use: for very small distances.

If you have trouble with selfshadowing causing artefacts, the usual way to fix this is with Shadow Min bias in the lights. One disadvantage of adjusting the min bias here is that it affects all objects - so raising it may cause loss of shadows in other areas. But you can avoid it by scaling the figures larger (with a group). Now the minimum distances have become larger and the min bias does not need to be adjusted because it is a "fixed" distance and is not affected by the scaling.

Simple tricks you learn over time