Doubly added score elements do not avoid each other.

1. In note input mode, after entering a note click on a dynamic in the pallet.
2. Click on another dynamic.

Result, the two dynamics are superimposed.

or...

1a. When not in note input mode, select a range and click on a line (e.g. cresc. hairpin)
2a. Click on another line (eg. desc. hairpin)

Result: the two lines are superimposed

These two examples are merely to demonstrate what is happening: collision avoidance is not activated in these cases.

In the examples it is easy to see that two elements have been added. Hiowever the consequences if a duplicate item is added by mistakenly double clicking are more serious and the root cause of seemingly unrelated and difficult to diagnose problems (for example odd behaviour of voltas or dynamics). As duplicate items are exactly superimposed it is not possible to see that two elements have been added unless the user selects the element and moves it; in fact only moving the last-added and revealing the earlier added element beneath.

If the second of the duplicate items was forced to avoid the first item, its presence would become obvious to the user who could then take action to correct the mistake.

See #313977: Double clicking on a pallet item should not add two identical elements for other discussion on the topic.