It won't be accurate. The devs have already said that square-rigged ships can sail directly upwind, albeit more slowly than on other points of sail. So you'll be able to sail in a circle instead of being forced to tack. The tactical downside of reduced speed going directly upwind might result in players (and the AI?) using more-or-less realistic tactical choices in how they maneuver. That part remains to be seen. At any rate, it sounds like you're not going to be at risk of going into irons, being driven astern, etc. if you blow a maneuver.
Supposedly this decision was made because they thought players would be confused, if they sent an order for a ship to "go to point X" and the ship immediately turned away from that direction, in order to tack towards it against the wind. It's not how I would have designed it, but it isn't my game. It's disappointing... but I want to see if the game is still fun, in spite of that.
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