Working as Intended or RNG Anomaly?

Just finished a battle with tiers 7-9 represented, me in my tier 8 Chapayev. I landed a total of 153 HE rounds on 7 different enemy ships, mostly battleships. Excluding fires, my HE rounds did a paltry 30,250 total damage for an average damage of 197 per round. Are you kidding me? The rounds in most cases were fired from a range of 10km or more in a high arc, so they would have landed on the decks or superstructures. I started 10 fires for 29,650 damage. Adding the fire damage, the average damage per shell is 391 per shell. Whoopy ding. Conversely, enemy damage to me was 36,858 from a total of 11 shells landed. An average of 3,350 damage per round landed. Is this just an anomaly due to RNG or is this "working as intended? Seems a rather ridiculous disparity in outcome for the effort given.