Are you talking about moving troops on rail or moving supplies on rail? It takes only one supply train to keep every unit in the Crimea supplied if you can keep it running 24/7. But it takes 40 times more trains to move a division. And again, it takes 'stuff' to keep the trains rolling. What would you rather ship in? What the Army needs to survive or what you need to keep your choo choos running?
As far as I can tell from all my reading supply was never a problem for the Soviets in the Crimea probably because of how the battle there unfolded. Nor was moving troops since it was a small theater. Distances were relatively small.
BTW, do you really think they were worried about shipping rolling stock, engines, maintanance supplies and fuel to the Crimea when a third of all the rail capacity was being used to move industry AND troops were being moved all over the 'mainland' from one crises to another? Really?
Small theater. Short distances. Relatively few troops. The whole of the Crimea should be supplied as long as there's a port to move the supplies through. I don't see a problem other than game engine limitations.
For starters I'm generalising about rail nets cut off from the main net, however that might be defined. The size of the cut off rail net may be, and in my experience is, considerably larger than the historical Crimean theatre of 41-2, as I have detailed. Surely there is more than a loose relation between the number of railyards and size and the rail net cut off, and the amount of potential rail capacity one might expect to find on a rail 'sub-net'.
I'm talking primarily supply, though I can't see why troop and supply movement capability would be mutually exclusive whatever the quantities of rolling stock involved. Rolling stock cut off from the main net does not disappear by virtue of being cut off, does it? If 40 locomotives are cut off along with all the other stuff needed, you have capacity to move troops en masse. If not, maybe you don't. It strikes me, then, that rail capacity should be determined by railyards attached to the net.
Supply and troop movemnent by train is logistically more economical than movement by road so supplies (which may or may not need to be shipped in) used to sustain a cut off rail net may well be less than the petrol and forage needed to sustain a horse/vehicle transport net. Do you think horses don't need to be fed and maintained, their carts maintained and repaired? I question, then, the validity of the choice you present, between supplying your army or supplying your trains. No logistics network runs on good will alone.
In my Crimea theatre, there are a number of ports and a substantial rail net and the railyard in Sebastopol as mentioned. I find it tedious and disadvantageous to have to march troops to the ports to refit and then march them back again. It seems obvious to me that with 50% of existing formations unavailable at any time, in such a situation a side would make every effort to utilise their rail net. It's fast, economical in supplies, and economical keeping formations active in the front line, but the game doesn't allow it.
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