FLYBOYJ
"THE GREAT GAZOO"
Well, the P38 didn't have a critical engine because it didn't have a better performing engine (inboard turning) of the two. Pfactor is the result of an an effective AOA change of a tilted prop disc. Tip a prop disc back . . . say, ten degrees . . . and maintain its horizontal direction and the down going blade has a higher angle of attack (pitch) than the up going blade. This has the effect of moving the thrust line from the prop axis horizontally towards the down going blade. Whether this is towards or away from aircraft centerline determines how much rudder (drag) is required to maintain neutral yaw. With both engines running the inboard wing sections would have a higher effective AOA than the outboard sections (spiral slipstream affect) which would help stalls start inboard where they should. With the surplus of power the P38 had as well as reasonable yaw control this was seen as a good compromise. The P82 adopted the same approach initially but stall performance was so benign North American switched the engines so both engines gave superior single engine performance.
OK...........
As stated, the P-38 did not have a critical engine.............