Most definitely cheating.
Possibly the cheat I hate more than any other in the game.
All it shows is that a player does not know how to sail, and does not care to LEARN how to sail. It is not all that difficult to sink hunters and warships, after a few times practicing. We do it often with as little as one gunner. More is faster of course). I used to heckle mates who did it, but I realized there was no point to that, and I try to be nice
Their loss, they'll never learn to sail.