IvanK,
The early version of the Mk II manual, which Crumpp is quoting, is for the planes with Rotol props only before the CoG limits were revised. Later the planes (any early Spitfire) with the Rotol props got tighter aft limits, 7.5" aft datum with atandard elevator and without bob weight, while the planes with the DeHavilland prop only got limitations for extended CoG limits, bob weigh required if CoG 7.9" aft datum. In other words bob weigh was not required for the planes with DeHavilland propeller.
The later manual you are quoting is for the Mk IIs with both propellers, Rotol and DeHavilland, after the CoG limits were revised, hence no warnings about the elevator control reversal. Note that longitudal instability and elevator control reversal are related to each other and CoG but not the same thing.
As pointed out earlier with documentation and calculations, the NACA tested Spitfire had the CoG at 7.8" aft CoG and Rotol prop, in other words the CoG was behind the limits and the results are not representative for all the early Spitfires nor all CoG positions.
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