Yeah I have set my CB's and DM to do it with good success so far but it only makes sense to do it like that because if you have everyone doing it you're just doing man marking lol. The difference being that your RB wouldn't follow a roaming LW out of his zone. I've just started with Arsenal and I've set myself the task of attacking like Barca but defending like a Mourinho team (I know I'm a glutton for punishment) we keep the ball well and the combination of targeted tight zonal marking, zonal marking and every player bar the CB'c and DM closing down the whole pitch is looking promising.