Its exactly the same principle on the MFI as on the EFI though, it appears as an air leak to both systems.
Both engines use an air flow meter, which measures the amount of air flowing into the engine, and adds fuel accordingly. The MFI one is cruder sure, but exactly the same thing happens when the DV opens. A quantity of air is dumped (ie leaked) and never reaches the engine, but that air has already been measured, and so the injection system adds the amount of fuel required for the air that should have been there, causing the engine to momentarily go mega rich, at exactly the same moment that you've closed the throttle. This invariably means the engine with cough, splutter, flat spot or even stall if you happen to dip the clutch at the wrong moment.
Obviously the EFI management systems are more clever, and have more bells and whistles to try to keep the engine running when that occurs, and are also faster acting than K-Jet, so will likely manage to handle it a little better, but its still just as bad for the motor as it is on the escort!