...I agree that research past MM will allow your partner to build more buildings, they almost always build hospitals and bunkers once available. I tried to avoid research in my games, but I don't see that there is any way to prevent your partner from researching new techs. I guess you could micromanage your AI partner and have them research each available tech until it is 1 turn away from finishing and then ask them to switch...
Would you do that to your partner !?


I did that too. In fact I did much more than that:
I asked my partner for all his gpt. When he gave it to me, he had to reduce his science slider, so he had more money available for trade. So I asked for all his gpt again… till his science bar was at 0%.
I also built a bunch of workers and sent them to his lands. Every town was farmed/watermilled. I wanted him to work hammers and specialists, not commerce. Now and then he would rebuild a cottage… which my workers would very soon remove.