Are the sparks flying again at ArcelorMittal? The world’s biggest steel maker by production is a shadow of its former self: its shares have tumbled 80 per cent in five years. The group is addressing its troubling debt position, as is clear from Wednesday’s annual results presentation. Now it needs to prove that the restructuring efforts it is undertaking to address chronic overcapacity and high costs in the steel industry in the U.S. and Europe are actually delivering results.