For best chilling you want to maximize the area, maximize the Delta-T, and maximize the flow.
If you flow over about 1 quart/minute, you probably have turbulent flow in the chiller - got that from the HBD a long time ago. Turbulence mixes the cooling water, so you don't have a stratified temp inside the coil.
You also need to get the wort moving to keep it from being stratified.
This looks like a gimmic to me.