John; I’m not sure nostalgia would be the best way to describe it but; your mention of railroad transit applications brought back a wave of memories.
In the late ‘70’s; I was with a grain exporter along the Houston Ship Channel. One of my tasks was the transit claims for grain that had moved by rail to say an elevator in Oklahoma, was unloaded and stored, then reloaded and shipped to Houston for export. As you note in your post; the railroads had special transit tariffs that allowed us to apply freight paid inbound to the country elevator against the export rate from there to Houston.
I worked in the grain industry for only 3 years before shifting to mining and then chemicals. In my 38 years in the latter two industries; I’ve not seen any transit applications and I’m pretty sure the railroads did away with them.
Curt