Originally posted by willj
Maybe I'm misunderstanding him, but I think what Homie was saying was that when the least amount of turns left possible is 2, lower the science rate all the way down as far as it can go while still having 2 turns left.
However, it doesn't just start at 2. If you want to earn the greatest possible amount of gold, check every single turn since you start researching to see the lowest the bar can go while still having the least possible amount of turns left.
OK, my interpretation was when the least amount of turns left possible while still maintaining a positive net income is 2. At this point there can be two choices: Either maintain a positive net income and lower the slider as much as possible and maintain 2 turns left. Or raise the slider to finish the research one turn earlier take a one turn income deficit. You have to weigh whether or not it is worth it to you to get the tech one turn earlier at the cost of some gold for that turn. Like I said, this is not always an option if either you're already researching in four turns, or if you can't produce enough beakers.