Sorry it took so long for me to respond, but the ITAD descriptions I was talking about are in your 7/11 post where you show two signals (1 MTH & 1 Lionel) wired to DZ-1075 detectors and two signals (1 MTH & 1 Lionel) wired to ITADs. Both ITAD descriptions say they represent wiring for the "OLDER" ITAD product, but I think one of them is supposed to be the newer product. Or, are they both supposed to be for the "OLDER" ITAD product and just showing the differences between an MTH signal hook-up and a Lionel signal hook-up? What's confusing is that one description references a hook-up diagram for "NEWER" ITAD product "on the next page."
I whole-heartedly concur with your reading recommendations and track plan changes; "operating" can be so much more fun than "running." However, the 1964 version of "The Art of Model Railroading" is actually a re-do of an earlier version by the same name. Don't remember the year(s) of the earlier version, but I know the earlier version track plan had a turntable at Raymondale and the later version did not. I will bet, just like you, Ralph made changes after initial construction to improve operations, just like you!