Anglophile
Warlord
I always play on fully expanded maps and even with the appearance rates for iron and coal turned to the max - they are not exactly rare materials afterall - you still only get one coal/iron per 20-25 cities (or more if you build close). That makes the probability of getting both in the same city radius pretty small. I have built it exactly once and would disband a newish city or 2 if it meant being able to build it, but not a core city because as wonderful as it is, the lost investment and opportunity costs would be huge in disbanding a core city.