Drag editing on a EditorGUILayout.FloatField

I'm using a EditorGUILayout.FloatField with a label in a custom Editor, which works correctly when the user types the value in the box (in my case, it triggers a Repaint call to show the float value in the Scene view).

However, the same FloatField does not work when the user places the mouse cursor over the label and drags left/right to increase/decrease the value in the field: the value in the inspector changes correctly, but it does not trigger a Repaint (and thus fails to show the updated value in the Scene view).

I'm currently learning how to implement custom inspectors in the Editor, so I'm probably missing something; here is the code called inside the OnInspectorGUI method for the float field:

 EditorGUI.BeginChangeCheck();
 var f = EditorGUILayout.FloatField("Position on Curve", t);
 if (EditorGUI.EndChangeCheck())
 {
       this.t = f;
       inspector.Repaint();
 }

Please let me know if I should add some context and/or a few screenshots of what I'm trying to do.