The 58th Division ascribed Coming_to_believe their success to excellent training Practice , a good creeping barrage and smoke shell , which had thickened Change the mist and blinded Perception_active the German defenders ; gas shell barrages Use_firearm on the German reinforcement routes had depressed Cause_change_of_position_on_a_scale German morale .

These were widely ascribed Coming_to_believe to Britain 's sense Perception_active of humour .