It's a recommended and frequently used way of calming a nervous bunny. In the Vet Tech program I'm in, you are encouraged to trance a bunny to settle it for nail trimming or teeth trimming (in malocclused rabbits).

Now what's wierd is how you trance a chicken! You tuck their head under one wing, gently pick them up and swing them gently from side to side. Puts them right to sleep.