I think I found a flaw in AI behaviour:
once I had canoes and finished exploring the coast a bit to catch sea critters, I put 4 of my 5 canoes together with my general at the korean coast, blocking all sea tiles.
A korean city, size 10 had worked 5 of these and so Korea - as I expected - tried to counter by beelining to boat building and after reaching it, it built a canoe builders hut in its city. In its 2 cities 2 huge invasion armies gathered as well. I expected them to spam the 5 canoes in no time, filling them up and sending waves and waves abroad the japanese shore, (although I am not that afraid as each wave only had max 5 units loaded and my ships would sink some of theirs so the remaining units would be xp for my general (lol the canoes remind me of german subs from ww1)- but at home korea is quite a power, a 5 promotion general who had his experience from thousand years of raging barbs would face my troops much too soon as my general is still very young and mostly suicidal seabound^^
To make a long story short, AI never built a single boat, healer and stuff instead. last thing they built was a seaweed farm, which is why i want to call it the see-weed-farm-instead-of-boat trip-bug... the other screenshot shows all ruins I encountered --raging barbs/autoraze really helps to decrease turntimes at one point (only the strongest survive (and the techleader with the great wall) but perhaps it was the barb rebellion bug, I dont know. Might be more frequent with more barbs around in general...
gonna send my hunters in search of that suspected, legendary giant barbarian stack horde with like 100 units ploughing through deity AI meat. Hail Japan^^
Here's the savegame (SVN from just before animals were beamed home - I like it to have to bring them home I guess, so I am gonna stay at that version a bit and hereby request a game option for the old ways
lol I guess I'm more conservative than I thought I was), maybe you can bring the AI to be smart and build a boat finally, after all, I blocked all sea tiles of 2 of their 3 cities with one ship :exploit: