It works, but I have plenty of times when it does not. For example if there is alot of ships, it may get confused or if you shoot from a weird angle. If there was a way we could say what ship we intended to shoot, it could resolve that. Atleast thats how I think about, from a programming side and user side makes sense to me.
That is where the skill of sailing comes in. I can usually line up the exact ship I want without difficulty; I admit I miss sometimes. Of course that is provided that it doesn't bug with a backfire shot or more rarely the wrong direction shot bug. I really think the basic aim in sailing is fine and it's just a couple minor bugs that are at issue with broadsides. Of course there's lots of other sailing bugs like loot and SvS stuff etc...
No like I legit get up next to a ship and sometimes it shoots like a shot gun all over the place, and this happens more often on my left broadsides than my right.
I don't get a difference between port and starboard broadsides and while I haven't monitored the percentage of malfunctions I think it's less than 10% malfunctions. I feel like most of the malfunctions are when hunters are very close on my tail and that there is likely a relationship between them.