I thought about the usual scenarios. The usual problem is the train exiting a reversing section while another portion of the same train enters it at the far end. This causes one of the train to want to flip the auto reversing one way while the other end is trying to get it to go the other way. Both ends of the reversing section are competing with itself and causes a short.
Now let's think about 2 separate auto reversing sections separated by a fixed polarity section, say 18" long. A train with lighted passenger cars, leaving reversing section #1, enters the fixed polarity section of track. If need be, the auto reverser #1 switches and all is well. It travels through the fixed polarity section, that let's assume is the length of a Big Boy. The train then enters reversing section #2. If need be the #2 auto reverser switches. #1 is still fine and stays put. In this situation, #1 and #2 are not competing with each other.
Any other thoughts anyone?