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And the P47's CSP is going to drop too, blackberry. I like the idea you present with modeling efficiency. Problem is you are making the same mistake the NACA did in adopting the 16 series. The calculations just did not bear out and give good agreement with the air.
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My estimate is below, please correct me if I'm wrong.
Efficiency: assume 3-blade naca16= 3-blade clark= 3-blade gotingen @0.7Mach
4-Blade naca of P47=88% at 0.4 Mach
3-Blade naca of P47=82% at 0.4 Mach
(See P47 data I'v posted)
3-Blade naca of P47d=63% at 0.7 Mach (out of envelop,so <80%) see data posted
3-Blade naca/gottingen of fw190A5= 50% at 0.7 Mach (3.3 m diameter, bigger advance ratio)
3-Blade naca/gottingen of fw190A8= 40% at 0.7 Mach(wide blade even lose 8% at Vmax)
4-Blade naca of P47=?????% at 0.7 Mach????? It should be bigger than 63% or not? It seems that US has never unclassified the 4-blade NACA16 high Mach number wind tunnel data. 
Do they want to cover something? But they did make the decision of choosing 4-blade In WWII.
If 70%, there is 30% efficiency advantage over fw190A8, this could explain a lot of 45 degree dive test in history.