It doesn't matter how the map is, people who break the rules are going to do so anywhere. Sometimes, in these new maps, there's a shield-wall set up and everything's going smooth, but there's always some players who can't participate because there is just no space for everyone to fight. But that does not mean that, if I am one of those people behind, I will decide to leech since I can't do anything else. Either I try to charge through the shield-wall out of desperation or I leave the server.
So you shouldn't be blaming grieving on Fips' maps but on people themselves. It might be true that a good map where each and every player can fight discourages grieving, but, in the old DTV, there were always people grieving anyway. Arseholes will be arseholes everywhere.