AccuDraw, via tentative points, lets you preview and constrain pending data point locations. In response to your input in the AccuDraw window, dynamic update in view windows lets you visualize the results. This gives you the option of accepting the displayed tentative point, or trying another location. That is, you have the flexibility to unconstrain a pending data point at any time. It is only when you actually enter a data point that you are committed to the values in the AccuDraw window and their results.