But compare the consequences when you make a mistake when doing that. Spitfires have a high tendency of falling into a tail-hurling flatspin, and the P-51s also have a tendency to spin in a violent manner.
The turning momentum is discontinued when that happens, and you have to correct your plane's attitude and resume turning - which by the time your plane resumes turning, it lost a lot of ground, and a firing solution will probably never be gained again. You "lost the turn fight" - time to straighten out, accelerate full, and run away.
The P-38 can pull much harder than the other planes, and it will just "mush" when it goes over the edge. No wobbling or destabilization. The plane still "turns" even if it stalls. Only when a lot of rudder is applied, or in a very tight downwards turn, the P-38 will ever go into a spin.