i just thought of this and i think it is quite useful
say you are behind in the tech race and have contact with several civilizations. the next civ that you contact may now trade you communications to civs they haven't met yet in exchange for one of yours. problem with ai is that they talk and trade among themselves.
so say trade comm to china(theirs) for comm to france(yours). then talk to china and trade them comm to france(again) for say comm to USA. repeat again and again but only trading the communication you have to one civ(in this case france). they will trade this in the next turn so trade it yourself to all of these civs in a turn. you can then use your other communication commodities to buy techs you don't have from these other civs.
i did use this in my recent game. problem was i was one of the top civs in the tech race so i just opted for gold. don't hold back. you'll lose this trading commodity anyway in a few turns if you don't cash it in.
say you are behind in the tech race and have contact with several civilizations. the next civ that you contact may now trade you communications to civs they haven't met yet in exchange for one of yours. problem with ai is that they talk and trade among themselves.
so say trade comm to china(theirs) for comm to france(yours). then talk to china and trade them comm to france(again) for say comm to USA. repeat again and again but only trading the communication you have to one civ(in this case france). they will trade this in the next turn so trade it yourself to all of these civs in a turn. you can then use your other communication commodities to buy techs you don't have from these other civs.
i did use this in my recent game. problem was i was one of the top civs in the tech race so i just opted for gold. don't hold back. you'll lose this trading commodity anyway in a few turns if you don't cash it in.