Sorry I am catching up on this late. The information regarding the whirlpool jets is very interesting and makes sense. These jets take a lot of water volume. I will have to check mine tonight. SD must have definitely made some plumbing changes regarding the intakes as my pump two uses all three. They put the new bearingless jets in 2003. I have the older style. The newer models also return water from the circ pump/ozone/heater through a large jet on the bottom of the spa which also serves as the main drain. My 2002 uses a return jet on the side of the shell and drain through the footwell intakes.
It is great having lots of Optima owners here.
