RigaMortus2
First Post
This is no different in 4E. Monsters can just as easily run/fly/teleport past a defender as they could in 3E, and at high levels it's even easier since you won't have an enlarged spiked-chain-wielding fighter who owns a 40x40 foot chunk of the battlefield.
If the monster is running around, it's making one attack instead of maybe 6 or more. It's a very stupid thing for the monster to do as wizards can walk around and still cast spells, fighters can use bows, leap attack, slashing flurry, spring attack etc.
Disengaging the fighter means the monster gets tripped and a free attack. Disintegrating wizards need to get past spell resistance and the monster needs to roll a 1 on it's fort save and if the planets align the wizard will do the same damage as the fighter.
4E defenders are less sticky than decent 3E meleers who actually bothered to try to be sticky. And yes, marks are nice, marking the BBEG then running and hiding behind the wizard who has a higher AC so the game becomes a ring-around-the-rosey can be quite amusing, but mechanically, nah. Trips, grapples and 3 or more attacks of opportunity as the monster tries to leave your zone... THAT is protecting your party and being mechanically sticky.

I have nothing constructive to add. Just wanted to say, thanks for the chuckle.