Bamspeedy
CheeseBob
ROP Attack Exploit:
The reason that I have never done the ROP attack exploit is because I've never had enough forces to pull it off.
It would seem to me that if you have enough forces to park outside every city that the AI have (Do you have to use espionage to look at the target cities to ensure you have your forces deployed according to your adversaries defenses? That may not be so cheap!). Then declare war and win every city in one turn that you were going to win the war anyway! This does have the added benefit of preventing culture flipping back to the targeted AI but there are ways to deal with that problem in other ways also.
Anyway, I think this sort of blitzkrieg tactic is "war legal", in a turn based game.
Well, I'm sure most people don't take out all the cities in one turn although it has been done. Most people just park a stack next to the civ's capital and maybe a few other high production cities. You can use your embassy and investigate city to find out their garrison, which usually is only 2 or 3 units. Then it's rather cheap.
Plus, it gives the AI absolutely no time to respond. It may not be honarable to not give the AI time to respond, but if I want to pull of a warrior rush, I won't give him a notice of war, so he can't pop-rush a spearman, for example.
I'm not saying whether or not this is an exploit, just clarifying what is being done.
ICS [Infinite City Sprawl]:
I have used ICS and it is very powerful. However, you have to focus alot of resources that may be better focused on other developmental areas such as military, expansion, or economic endeavors. I look at ICS as a milking and/or cultural tactic. The more cities that you have the faster you can get to a 100,000 cultural victory. I doubt I would use ICS for a conquest or domination type of victory.
It could be used for conquest or domination, also. Just look at Aeson's games. Although you do, generally need a good map and/or low difficulty for this to work, though. In GOTM6 and his HoF game, he created a settler flood. Build cities extremely close, and every city building another settler and a few workers, here and there to build roads. It doesn't take long before you have hundreds of cities and make so much money, you can rush whatever military units you need. Later in the game, when you need bigger cities for production, you could disband some of the cities.