This strategy is not aimed for colonial age, but later. Industrial is too late. I don't remember the age3, but is the good one for doing it, send army to attack (Serbian army last enough), and citicens to build houses on another point, 6 villagers will be enough to survive and build 2 houses. Enemy's economy will be severly damaged now that more wood is need to replace buildings, villager that were gathering resources are now extinguishing fires so your gather rate drops, perhaps some die or get very hurt, so at the 3 third time you do this, the enemy won't hold on. It is very simple. By the third or fourth time, the enemy's economy is just too stretched and cannot hold making new units, extinguishing, gathering, and building at the same time. It is a win by economy exhaustion by an offense by fire.