I'm foreseeing one possible terrible minecart unexpected behavior (not going to call it a bug, because it only kind of is). Suppose you're moving stone. Your dwarves move it to a receiving stockpile and throw it from there into the cart. The cart transports it halfway across the map. At the initial end, they run out of stone. Dwarves at the terminus pick up the transported stone and start hauling it all the way back to the initial stockpile to keep it full.
That wouldn't be a bug though. Thats all working as expected. It just defies real world logic and real world common sense.
Plus you could totally stop that from happening with burrows.
Well, from the way it's described in today's devlog, it doesn't seem either illogical nor a big problem...
Each stop gets a list of stockpile parameters, and the stops can be linked to stockpiles and given conditions before the vehicle is set to depart.
Seemingly certain stockpiles shall be linked to routes, so I wouldn't expect the non-sanctioned-stockpile-to-stockpile hauling you mentioned to ever happen. I could be wrong, but stockpile-to-stockpile hauling doesn't even happen now, right? It seems possible that
workshops may prompt hauling from distant stockpiles, but then one would assume that works just as it does now, in which case there wouldn't be any closer material so your fort design was borked in the first place. There doesn't seem to be much reason to worry here.
What would be rather cool would be if workshops could be linked to stockpiles too, to really lock down the production chain.
(edit - just checked the wiki and I did not know that you can already specify stockpile-to-stockpile hauling, but it does have to be designated by the player, man I feel bad I didn't know that!
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