Imagine this: (you'll have to because I didn't have camera handy) Juvenile LW in Buddlejah chirping away to be fed. Magpie on branch above.
Then, in a well-executed pincer movement, one parent from the left, one from the right, dived toward magpie at high speed and knocked it off its perch.
Warm work it seems.
Here's one of the well-protected juveniles after the event.