I have never seen a thread about this and I think this could help. Well, I'm not talking about choke points. In civ4, the key to stop all enemies/rushers was not to put units in choke points, but go straight to the enemy territory, declaring war. You will need maybe only a choke point or 2 instead of 5-6 if you have a huge continent. This works all times because your enemy will be stopped in his enemy, with a huge block of production/growth and science, and he will need a lot of units to expand to prevent that you stole a settler. Try to follow these tips:
-1 Build 2-3 warriors and send them in the 2 forests in the enemy territory. If you block his production he will need a huge amount of food to have the same production.
-2 Never attack his units, only look at what he is doing 5-10 turns before he comes to your territory, if he wants to attack you.
-3 Never try to attack his capital if you have an attack of 1-2 against the same, that would be a suicide.
-4 If he moves undefended settlers attack him if you are sure you can kill him.
-5 If he build a settler, you could move your warriors at the end of the turn to block his food production, and he will have 1-2 pop, very low
At the moment I think this is ok as help, and I hope you appreciate this, if you are fast you can block rushers, and expand fast. If he wants to attack your city and you know you have enough production to build defences, don't try to stop his armies, but you have to press him. If you wait him, he will press you, if you press him, you can expand