There was a loooooooooong discussion about this. The map doesn't assume roads in every WitE hex so much as assume their absence. Neither does it differentiate between the relative road density and quality of the west vs scarcity and poor quality of the east.
It was frequently stated, as above, that roads are represented by changing terrain type. So, if the Moscow-Smolensk highway (a road generally considered of aproximately European quality) runs through a hex that would otherwise be considered wood, that hex becomes clear. That's my understanding anyway. This gives a tactical value to the road that it shouldn't have, in my view. If the same principle were applied to western Europe of the time, virtually the whole map is going to be clear hexes.
The point I've always argued is that though sparse and bad, there were Russian equivalents to roads that served some of a road's universal function, primarily in crossing obstacles for and accelerating in all but the worst weather conditions, wheeled transport. They would not be considered present in every hex though.
I would accept that a ten mile hex may be too large a scale to represent pictorially, all roads that might deserve represntation. In the west, that would make the map a mess. That doesn't mean that they can't be represented though. The issue is to differentiate tactical from logistical use and represent roads in such a way that compliments a new and overdue representation of logistics. It has been shown that the absence of logistical representation leads to all number of historically impossible situations, such as ridiculous unit concentrations. Even old War in Europe had major and minor ports. We just have ports.
I advocate a new map layer which models maximum supply throughput and infrastructure deterioration through use, in every hex. Logistics is where roads really come in to the game, or should do. All those road construction battalions that are currently used to repair rail lines will then be put to their proper use, repairing, maintaining and building roads. That's what they did historically, because that's what the armies needed.
Players would then have to think carefully about how many divisions they sent to an area, and how they would be supplied. Advances would then tend to follow routes that could be supplied. Stockpiles would need revisiting.
“The end of democracy and the defeat of the American Revolution will occur when government falls into the hands of lending institutions and moneyed incorporations.”
¯ Thomas Jefferson