The reason I suggested that some of the local NM rail historian weigh in here to give data that the dismantling happened in 1941 was that it should be easier and quicker to find than when it was intended to be hidden to protect the Manhattan Project. No one was to speak of the work going on and efforts were taken to hide any construction activities.
There could be a reliable 'Con' fact right in the railfan's collection. I thought it is more likely to prove the ‘con’ than the 'pro' Secret Operation theory.
A useful “Con” fact just came in with the dates of the AFE for retirement of the coal bin and turntable at Embudo in March 1940. This is not proof either way as just that helper engines were no longer used. We know the line still ran a year and half after turntable removal.
Recent news is that the Embudo stone faced station got some money and is no longer up for sale, but again serving meals.