The sentence of the rule book: “If Flyers wishes to Break Away from Close Combat, it does not to roll anything, even if an enemy model wishes to prevent it." is in this case obsolete because it only works for vehicles and this is already stated below on the same page.
dmcgee1 : “Auto Break away is, well, just that. A vehicle may Auto-break from CC, no matter the circumstance. Tangle Chains, Chains of Illian, etc. have the effect of negating the attempt to break away. With vehicles, there is no attempt, they merely drive (fly, roll, hop, walk) away.”
OK, but how does it work if the vehicle is surrounded by enemies. There are no rules to knock over people like in the editions before and the rule book says in general you need a gap of 4”. You never get out of this CC with or without the chains. Is this correct?
The chains works against the Praetorian Behemoth and the Mercurian Maculator, too. Why shouldn't it work against vehicles, too?