Me 109 compared to Soviet fighters' manoueverability

[spiculum]

I asked the same question at another forum where someone responded "The wing design (of soviet fighters) allowed them to hang in turns under full control when the root was stalled or partially stalled.
They also had the wing designed to keep the ailerons effective through stall."
I asked what aerodynamical feature the triangular wing geometry of Yaks and Lavochkins gave them this advantage and why other nations haven't adopted it.
But he could not give an answer.
Maybe someone here knows?