Originally posted by umop-apisdn:

I get where you're coming from, but... physics.

When pulling a trailer, even a truck designed to do so has grade restrictions and isn't typically able to haul on a slope higher than a 10% grade (and even that <6 degree slope is considered "extreme"); the principle of the inclined plane says lowering the angle of motion decreases the work* required to lift an object.

Far from "leveling the whole side of a mountain", you're just making roads that are actually traversable under load.

If it's that big a deal, just fill your inventory, jump on a saddled (and tamed) lox, and go wherever you want at full speed.

* by which I mean the scientific definition of "work", measured in joules (ie, one newton per meter, approximately 0.7377 foot-pounds).

Indeed. That's why the Union Pacific railroad spent a LOT of money on a survey going through the Rocky Mountains. No place they laid rails in that area has a grade greater than 2 degrees. That's why the Moffat Tunnel goes under the continental divide where it does and why the Big 10 Curve coming out of the Denver station goes around in a 270 degree arc as it begins the climb into the mountains. This allows the California Zephyr to travel at 55 MPH through the mountains though they limit the speed to 30-35 MPH because of winds and they have welded concrete filled rail cars to the sidings as wind breaks in the worst windswept areas.

@OP You can haul about twice your total carry weight up a 26 degree slope with the cart (the slope of wooden and stone stairs). You'll have to alternate between sprinting and walking to get over any rough patches.

The purpose of the cart isn't to go up and down hills. It designed to go from shore to shore between hills so you can go across a small amount of land instead of sailing all the way around all or part of an island or to go from your dock to your smelter. The devs try to keep realism for immersive purposes where they can. Its even possible to build small bridges across the small rivers. Some creativity and exposed boulders can allow you to build a bridge across a large river.

If you are wanting to move large amounts of silver ore down from the mountains you can take the materials to build a cart up with you, build the cart, fill it with silver, push the cart over the side of the mountain then go down and pick up the broken bits of the cart and the crates of silver, rebuild the cart, and then go from the foothills to your destination.

Alternatively you can build a portal at the top of the mountain that connects to a portal at the bottom of the mountain, chuck the ore over the edge, portal down and pick it up, then keep going to the shore where you parked your long boat.