Point, linear, polar, XY, and rotation parameters have a property called Chain Actions. This property affects the parameter behavior if the parameter is part of an action's selection set.
For example, you might include a point parameter in the selection set of a stretch action that is associated with a linear parameter. When the linear parameter is edited in a block reference, its associated stretch action triggers a change in its selection set. Because the point parameter is included in the selection set, the point parameter is edited by the change in the linear parameter.
The following example shows a block definition in the Block Editor. The point parameter (labeled Position) is included in the stretch action's selection set.
If the Chain Actions property for the point parameter is set to Yes, a change in the linear parameter will trigger the move action associated with the point parameter, just as if you edited the point parameter in the block reference through a grip or custom property.
If the Chain Actions property is set to No, the point parameter's associated move action is not triggered by the changes to the linear parameter. Thus, the circle doesn't move.