I do not doubt that the 190D and 152A are similar, but your contention is that they are the same aircraft, which they are not.
Harmann's book doesn't specifically compare them, but from the remarks section for each prototype, I can see the following definite differences: Different tail from the 190D, longer fuselage, added an engine cannon, different wing area, use of the Jumo 213 with a three-gear transmission and two-stage supercharger. The prototypes were converted from former Fw 190 A-0 production machines (not Ds). There are certainly other unmentioned differences as well.
Moreover, the RLM specifically ordered the 190D into production, rather than the Ta152A, per Harmann's summary.
In any event, I view the 190D9 itself as being most of the way to "new plane" status. Can you imagine taking a Mustang, adding a P&W RW2800 radial engine, changing the tail, modifying the gun package, lengthening the fuselage, and still calling it a Mustang? And, as if that were not enough, you go on to modify it by changing the wings and other things on later prototypes?
PS - Harmann's book is definitely a better source than Jane's.
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SnakeEyes
o-o-o-
=4th Fighter Group=
[This message has been edited by SnakeEyes (edited 11-01-2000).]