I guess we can agree to disagree on the semantics of the downforce thing.

No reducing lift does not create downforce. That would require something that actually forces down the car, not simply reducing the tendency to lift due to aerodynamics.

The spoiler negates the lift, but does not generate additional downward force

This is exactly what made me think of the aftermarket spoiler. Unlike the OEM unit, it is just a wing that sits atop the struts that raise it--meaning it's effect would be minimal once deployed.

I think I'll try pulling the fuse for it before driving home today and see how the car feels when the spoiler isn't deployed, just sitting against the body.

The other test could be to deploy it, pull the spoiler fuse, and then block the opening between the struts like the OEM unit does to see if there is any impact.

Straying a bit off topic... I thought for sure that our 986 spoiler would make the list ;)
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