I replayed Moonsinger's Sid HOF game from 4000BC and I fall behind in techs every time by 1000 BC -- I've done multiple replays. Persia is always the run away tech leader and has the Pyramids. If anyone is able to replay this and keep up with techs by trading, I would love to hear how. I research at 10% and start off with Alphabet then Writing. By the time I am done Writing, Persia already has the Republic and Map Making. I contact Korea near 1000BC and they are slightly behind Persia, but still far enough ahead that I have nothing to trade them.