Interesting, looks like I have a lot to learn.

I think I remember oil being introduced to the game, but it's impact was negligible at the time.

So what exactly is oil for, if you dont mind my asking. What is oil burning?

And yeah, you are not wrong about the techer strat. It was fully dependent upon land grabbing. Get as much as you can, tech out every turn possible, sell and buy what you need. There were thousands of countries at the time, so there was never a shortage of people to attack. It looks like now exploring strats might be a lot more viable than they used to be.