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If not, would a ruleset change allow that in 3.0?
WW2 France and Balkans had recorded instances of that.
Likewise, why was General Sherman's March to the Sea 60 miles wide? 'Cause there were two Confederate railroads that distance apart. Of course Sherman's Army would have have been protecting "engineers" that were destroying every piece of iron, heating rails in the center, and bending it around a tree and letting it cool, while still around the tree. Of course Grant and Sherman were very concerned about their supply line from the Ohio river south to Nashville, and on to Chattanooga, as Sherman was marching on Atlanta. That supply line was very vulnerable to raiders as it penetrated the Confederacy. The raiders did attack, but Sherman had very good (hardened) "engineers" that could replace a burned bridge in less than a week.

Forgot to mention that Sherman built the equivalent of fortresses on the line south from Nashville. Not that it helped that much. The Union soldiers weren't effective against Forrest's Calvary Corp who destroyed sections of that line multiple times just to see Sherman's engineers rebuild it, without affecting the logistics of the front line soldiers nearing Atlanta.

My discussion of the Civil War railroading is a summary of a book titled "Victory Road the Rails" by George Turner

In 3.0, that depends on "CanPillage" unit class flag + if the extra is removable by "Pillage"
In 3.1 and later it's controlled by "Pillage" action enabler + if the extra is removable by "Pillage"

In most rulesets, land units can pillage, and Road and Railroad have "Pillage" rmcause.