Yes, this. As I say, I only did it a few times out of curiosity or when my team was crap. We were never going to win the objective anyway so I went for a wander.
therefore it's not a true 256 multiplayer as the game forces you to stay within a section of the map going for your set out objective as part of 1 squad. it only ever worked in the domination part of the game too, other game modes had much lesser players as a whole, 128 players and then 64 players, which were also usually split up into teams and squads.
a true 256 multiplayer would let you do whatever you want on whatever part of the map.
the only reason the game worked was because it used dedicated servers and forced people to stay within a certain part of the map so not too many players were interacting within the same space at the same time.
even on PC the biggest i have seen on CSS is around 64 player servers with no lagg. any bigger than that and they lagg like hell and you can riddle people with bullets and nothing happens, due to server not being able to cope.
mw2 is horrible at times and even then that is only 32 player max on ps3, more games need dedicated servers. dedicated servers can take a laggy 32 player game running on p2p and turn it into a smooth experience for say 50 players.
run the dedicated servers for 1 year, then bring out a patch which switches to p2p after a year so people can continue playing online without being forced to pay for a new game.
this would be the best solution. but it would cost them more money and all they care about is profits it looks like.