Surely the value of variety in most contexts is of value? You can of course make the choices you do, and I hope you enjoy them, but the element of surprise in a musical gathering is important to me.

   A few tunes in the middle of a song session can lift the atmosphere and vice versa. A well-chosen poem or limbo dance can make the night!

A gathering I attended years ago developed into a fairly uninspired tune session - until an older lady asked if she could give a song. She turned out to have 'trodden the boards' in the past & gave us the liveliest version of the 'Laughing Policeman' I've ever heard- the whole night suddenly became fun, smiles and musicians talking to each other..... yes it was that good!

The highest quality unbroken singing or the equivalent uninterrupted tune sessions can be extremely monotonous- I have been there....