You guys are getting confused about how the Mocal thermostat works. No insult intended here - I was too when I first bought one. I had to call the dealer to explain how it worked because even holding it in my hand, it didn't make sense to me.
The key thing is that the thermostat doesn't work by positively blocking flow to the cooler when in the "cold" position. It only gives an alternate path (the bypass) for oil to go when cold. The oil follows the path of least resistance and more of it goes back to the tank than through the cooler due to the natural extra resistance of the cooler path. Then once warm, the bypass shuts, and oil can only flow through the "straight line" paths - engine/filter to cooler, and then cooler back to engine/tank.
The key thing with the Mocal is to have a straight path through the thermostat from the engine (filter in this case) to the cooler, and also a straight path through the Mocal from the cooler back to the engine/tank. Don't be misled into thinking the diagram is saying that flow through the bypass has to do that 180 turn for the thermostat to work correctly. It just has to flow from one side of the thermostat to the other.
I'll try to draw up a couple diagrams to show you what I mean.
Or just call Mocal if you'd prefer a real expert opinion
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Scott