This is interesting....

I have read that rhymes and song melody are processed by the right hemisphere of the brain. When you put words into those formats the message goes to the emotional centers better.

It is thought that the non-verbal right brain is responsible for many lingering bad feelings. This technique is used for people with aphasia also.

A friend of mine who was a social worker told me that much of therapy is talking out loud, and thereby reprocessing thoughts and feelings which then have to go thru the auditory channels.
This makes integration faster. For example if someone is upsetting you, and you write them a letter, you should read it outloud to yourself, to defuse your disturbed responses. Many people find that after that they don't need to send a letter at all!
If you keep a journal, reading it out loud, helps the same way.

Females have some small amount of verbal right brain abilities whereas males do not. So I think your therapist was being very creative.