To what extent are performers with extraordinary musical talent actually partnering with a divine-level being during shows and concerts?

This is perhaps larger than you would expect. We would say about 30% of the time there is an actual collaboration taking place. If you read descriptions of musicians, in describing their lives as performers, they will often tell you that something special happens when they are performing for an audience that seems to energize and transport them and, under those conditions, they will see something special happening.