If you have the resources, this is an option. In the early game especially, crafting bricks can be a pain, so I see why you'd want to cut down on the time taken to craft up all the bricks you're gonna need. You could have two or three furnaces running, all smelting bricks, though it might be an idea to have at least one spare furnace for smelting iron or anything else. There's no sense in stopping all your other production efforts just for bricks.