Overflow is probably one of the best maps to get this simply because you can have 2-3 players stack up on C Domination and 2-3 players on B Domination and the people near B Domination can still get to A Domination relatively easy.
The other way to get this is to have someone on your team get a VSAT/Dogs/Swarm in the first round but save it for the second round. Also make sure your team only captures a single flag the entire first round so you'll have enough time and very little score so you can do this in the second round. A lot of teams/players will back out once a VSAT/Dogs/Swarm comes into play, you just need to hope that at least one or two people stay in the lobby. --- PSN - W3tm0G XBL - xM0G
I wouldn't even attempt this without having at least two other people playing with me. The only time I can honestly say I've pulled this off in my Call of Duty career was playing Overgrown in Call of Duty 4. We managed to shut the other team out. In Black Ops, I came back from an ~80-point deficit on Radiation and won either 200-199 or 200-198. There's a strong possibility we held all three flags for three consecutive minutes. I happened to be solo for that game, but I had two teammates with 40+ kills. We never should have been in such a big hole.