I think you're correct.....The optimum recoil spring combo would allow for proper ejection, and allow the gun to lock back when empty.....and, the slide (spring tunnel) would not reach the frame during recoil.
There's a little window of motion for the slide itself between the slide lock position and impact with the frame, but not much. Almost have to tune the springs to the particular ammo you will be using.

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Ret. LE, FA Instr, S&W Armorer