By the time you've completed step #4, your opponent will know that there's trouble ahead. All of your pieces will be active, focusing their energy upon a single fixed point. By contrast, all of your opponent's pieces will be relative weak, defending rather than attacking a weakness.
The final step is simple enough. Attack the weakness with a pawn. As you can see in the diagram, black has a large quandry. We know that the d6-pawn has been fixed. Black cannot push the d6-pawn without losing it, and capturing the white pawn on c5 opens the d-file for white's heavy artillery. How would you proceed as white after ...dxc5?