Jack,
It's a case of time and place. I can easily talk for an hour on the provenance/history/geography of some of the songs I sing, but wouldn't dream of doing this in a singaround where you're often lucky to get 2 songs in. If I'm perfoming to a historical group I might do this but to people who've come to hear singing the briefest of intros suffices. I'm afraid I veer more towards Bob's colourful and brief statement.

And we'll all be glad when you've got to the end of the dictionary and got it out of your system.