To explain, I see a ship take heavy damage from SS torps, to the point that they begin
to take a tiny bit of HP damage.

Then, a Destroyer comes up, and while only doing 5 damage per shell, sinks a BB that
had nearly full green health with only about 10 low caliber shells. Each shell only
showed 5, but the actual damage dealt was somewhere between 500-1000

I've seen BBs with full health get sunk by a single shell while smoking