They get 150% additional trade power by modernising... Barques have 2 trade power... Great Frigates have 5 by the end of the game.
You seem to be neglecting the oars.
Oars require a lot of width. They'd triple the width of the galley - or galley like craft (see below). These wouldn't be kayaks with little paddles - oarsmen need lengthy oars to get a longer power stroke; a long power stroke means the craft accelerates faster, and has a higher top speed.
So the width of the oars isn't negotiable on a galley. Stowing oars is not feasible in a rowing competition, and it wouldn't be in galley combat either. The term 'dead-in-the-water' would apply. Stopping invites being rammed, boarded, or shot - or all three.
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Note the oar length, compared the width of the boat (scull). Competitive rowers use a paired-down scull/shell not unlike a tiny galley. (Thanks
https://rowing.at/)
So it's highly doubtful galleys would mass together. They'd get in each others way. The naval term for the result then would be 'fouling the oars', leading to the whole 'dead-in-the-water' scenario again.
I agree, though, that galleys would be comparatively agile in the earlier days of EU4's timeframe.
The scaleless sage is offering a very plausible interpretation here.
The predominant winds in the Mediterranean are northerlies - north-to-south. The seasonable variation doesn't change the direction much. Going back a thousand years or so, a journey from Athens to Alexandria could be something like a week going south, but over a month in going north. People seemed to rely on a convenient tail wind.
This implies that sailing ships weren't good at tacking i.e. they could not get much speed from it. And in combat, the a sailing ship might need to tack to-and-fro
quickly - particularly against Galleys. They might have been using lanteens which have a 'bad tack' where the sail has to press against the mast when going in one direction.
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Or they could have been just using square sails, with no tacking ability at all.
Either way, an oared ship could capitalise on it's comparative manoeuvrability; getting south of a sailing ship if the wind was a northerly, and cutting off the best line of retreat.
However, once a sailing ship's ability to tack quickly reaches anything like modern-day yachts, galleys become less advantageous.
I believe the large 'rounded hull' designs were encouraged because they could be refitted for warfare. Commerce and war were pretty closely linked for the Italian maritime powers (if remember rightly).
The 'heavy ship', 'light ship', 'transport' designations in EU4 are fun from a gameplay standpoint, but I don't think they're historical until we get to our 'two decker' type ships which sound more like pure military vessels.
But yes, your fluffy fishiness, please continue.
You're not concerned about propulsion? Seaworthiness in different conditions? Manoeuvrability? Navigation? Not even a little bit?
Or you should watch some sailing races? He who cannot move cannot fight. Get a feel for the speed of cutting-edge superyachts! The America's Cup competition begins in March next year - don't miss it!
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