I think G Double Tizzle was saying that he didn't notice a diference when he changed to the blue cluch. So that would meen that the old one was working just as good as the new. Just to clarify for ya
G Double Tizzle did not change the fluid or when the clutch plates opened, so the performance would be nearly indistinguishable from the black hub fan.
You can change the fluid and adjust the clutch plates on the black hub ones as well. That is the plan for the

I bought a new blue hub for mine, as mine had failed and I was unsure if it was repairable or not (most likely is), and didn't want to mess around with it in 100+ degree weather. Some fans have failed due to lack of fluid, and the clutch plates or bearings get damaged. Mine does not appear to be leaking, so it likely simply needs new fluid.
A little PM (new fluid) once every 10 years or so and it should never fail.