It is true.
I was "in my green metal suit preparing to shoot up the city" and, while nearing the city, I heard "trans europe express" (AHII mix) coming from the speakers..........so I went to turret and killed the locomotive and continued along the tracks to the city thinking I had left the train stranded.
Imagine my surprise when 3 minutes later I see a train spawn in front of me on the same track.
At that point, I was intrigued and sat equidistance from where I had killed the locomotive and where I saw the train magically spawn.
I spent 2 hours hitting the train and turning around to kill it again as it spawned a bit further toward the city.
Even though I was very near the city, trains would sometimes come in 3 minute intervals.
I also experimented with blowing up partial trains........or just the engine....or just from the coal car back while letting the engine go on.
For some reason.......I could always see the trains magically last seen entering the city even further down the tracks.
Does anybody have the lowdown on train behavior and whether killing them actually denies supply delivery?
It seems nothing related to the city, when destoryed, has any effect at all.
This is not a complaint.....I was very entertained during this tank sortie including reporting the 21 enemy bombers that passed overhead on the way to pound a knight field.
The bomber welcoming committee sure enjoyed the action.