/snip
Hussar, I'd be interested in knowing what you found that refutes this.
Sorry, wasn't clear. I was referring to the pre-3e version of Wall of Iron, which can be dispelled.
The thing is, with this tangent, most of these issues are not insurmountable. Smelting the iron is simply an engineering problem. Heck, the easiest thing, in my mind, to do would be to create the wall on the edge of a cliff, push it over and let it shatter on the ground below. It's iron - it's not like it has a whole lot of tensile strength when it's an inch thick sheet covering many square feet.
And, dispelling isn't a major issue either. Simply cast Wall Of Iron many times. Make sure that you keep the batches separate. Equip your soldiers from the batches and make sure that every group is made up of ten batches or more.
Now it's going to take about twenty dispel magics to remove the iron from a group. Which begs the question whether a broken up Wall of Iron could be affected by a single Dispel Magic or not - I don't know, that's a DM's call. But, in any case, it's still not a seriously big issue.
I'd be much more worried about that 5th level wizard hitting my troops with fireball than dispel magic.
KM - I see where you're going with it, but, my problem with 3e is that it's so poorly thought out. Most of the effects are based on adventuring. That's why continual light is such a low level spell - by 3rd or 4th level, screwing around with torches is a PITA, so, you smack out a couple of these babies and you're good to go. So on and so forth.
The spells were never designed as setting elements. And, frankly, the consequences of these spells were never explored in many of the settings either. As you said, it's effect as Myth. It doesn't change the world because it's part of the Myth of that world and we are just encouraged to accept it.