It's hard to see how the YAK3 manages to achieve all of this performance with no technology and without the usual trade offs.
Speed. The YAK3 is a low power airplane. 1290 HP is one of the lowest late war numbers. It's below the P-39. The Yak is not appreciably smaller than a Spitfire, or 109, or P-39 for that matter. It has no special wing features, like leading edge slats (109) to help it turn tightly, or razor thin leading edge wings to achieve low drag (Mustang). So how does it have a low drag speed wing, and high angle of attack turning wing at the same time? Where is the trade off?
Toughness. Yaks are tough...but light. Splits break wings off in high G turns, and fall apart when hit with bullets. The 109 also sacrifices toughness for lightness, and so does the Zero and other light planes that minimize weight to achieve performance. Does it have self sealing tanks? Armor plate? low gage skin and light weight wing spars? Why is this plane so light and what price in toughness is it paying for that lightness. Yak3 weight is close to the weight of a Zero, but they are tough like Jugs. Where's the trade-off?
Energy retention. The turny wing seems to bleed no energy in high G turns. Again How can it turn so tight with such a low drag wing?
So my point about the YAK3 is there seems to be no trade offs among the various performance aspects even though the plane is unremarkable from technology and engineering standpoint. No variable geometry wings, no water injection, no two stage supercharging, no kevlar or carbon fiber, no exotic wing design. Hard to see how this mystery plane achieves the performance numbers it does.