You will hopefully understand me not buying the +20 psi and 3500-3550 HP figures, in light of the docs available now.
Since Germans tried to stop the high-flying bombers and their escorts during the 2nd half of the ww2, I'd say that altitude performance was very important. It was for Germans, for Americans, and also for the RAF, who were the 1st people to push for 2-stage superchargers in military engines in Europe, and, with P&W, in the world. RAF were also the 1st to provide some sort of escort for the 8th AF.
No irony there - Americans have had money to buy stuff, and were using the stuff in the way they saw fit, even gifting them to the Allies.
If you think that turboed Sabre will come in cheap, I have the Brooklyn bridge on sale, real cheap.
Any source that describes the P-47s being considered for A2G by Soviets, the same Soviets whose fighters were hopeless in A2G? Any sources describing USAAF wanting the Typhoon?
The P-47s surely killed a lot of Axis ground assets for not being good at low level.
I have no reason to doubt the veracity of Wilkinson, esp' since the figures listed interrelate, so cannot be a mere typo/proof error.
Where are the Air Ministry Acceptance records - relating to 'Official Type Tests'? That would be the clincher.
The high-altitude war was an outlier, primarily due to the USAAF strategic bomber doctrine, most everywhere else, tactical air-power
was the thing, & certainly after the advent of the turbo-jet fighter, high-altitude capability for piston engine fighters wasn't a big deal.
As noted here recently, the US Services (& rightly so, IMO) put their own interests 1st, inc' Lend-Lease.
IIRC, the Soviet assessment of the P-47 (perhaps a member here, more up on VVS matters - can link it) was like a more extreme
reaction but essentially similar to the Eagle Squadron pilots who climbed out of diminutive, dainty Spitfires into the mighty 'Jug',
as going from a Yak to a P-47 would be, naturally enough. (The VVS were told P-47s were used for A2G).
The USAAF assessment had warned P-47 pilots to be aware of LW advantages over them below 20,000ft. Of course if the P-47 had
to drop its A2G ordnance early to contend with interception, that was 'a win' for the Germans not bombed as a result.
The figures for 9th AF tactical P-47 losses are pretty sobering stats, plus when redirected as escorts for mediums, they suffered too,
check the infamous B-26/P-47 attack during the German Ardennes offensive, when they were decimated by a LW interception.