It is an interesting article but doesn't cover all the issue of rail transportation in that the German's faced in the USSR:
1)For example, the German railroad workers remained working under their civilian contract even after the start of the invasion. As such, they literally took two weeks off in December for Christmas, virtually shutting down rail transportation/repair work on the Eastern front during this time.
2) Except in the Baltic States, where I don't have much information, the wide gauge use created a large number of engineering challenges to the Germans:
a) the rail bed did not need the stone/dedicated build up like the rest of Europe. The wide gauge, combined with the wider cars and wooden floors, didn't carry as much load and spread it out over a wider area within the cars. This resulted in the cars (and engines)not exerting the pounds per square inch on the track and track bed that the Western European trains did.
b) USSR rails were made of the sale quality of iron or steel as Western European rails and would buckle under European train weights.
c) And refueling/watering did require more stations to be build, even in shorter distances. On average, a Russian train required a water station every three water stops every 200 miles or so, a European train four.
d) The stamped metal bridges in Russia were simply not capable of taking the weight of many European trains - or at least, not for very long. And you literally couldn't just "move the rails" on these bridges. They were built into the bridges. And hundreds of bridges are simply not shown on the map due to smaller streams and rivers not being shown.
3) Russian signaling equipment was primitive - more primitive that most of us can imagine. They made up for it in manpower. It worked fine unless a train needed to "course correct" while underway or between stops. Then it failed miserably.
4) Virtually all transportation modes except water bulk out before weighting out. What does this mean? It means, for trains, the cars fill up before the weight limit is reached. So the broad gauge Russian cars ended up being more efficient in same ways than the European cars. Where they had issues centered on the floor. Due to material shortages, Russian rail cars were totally made of wood except for the bracing and wheels - and that included wooden floors. So if the carried really heavy things like artillery shells, they couldn't carry as much as a Western European car. If they carried people (troops) they could carry more. Flatcars, on both sides, had metal floors.
5) A double line, as a note, is four times as efficient as a single line if that line includes bridges and side rails for both lines and usually takes 11/2 times as long to build as a single line.
So, it is not as easy and just moving the rail lines and regauging to get the lines moving forward (although in the Baltic, it may be easier than that).