This is either a bug or an undocumented change.
Used to be, a DK could jump off a wall, immediately use chain pull on an enemy (before the DK started falling), and the enemy would get pulled down with the DK. It no longer works - the enemy will get briefly stunned when hit by the chain, but won't be moved. This removed one of the very few mechanics that could actually hurt a "blob" group, which is unfortunate.
How it used to work:
What it does now: