Hmmmmm
As audience I find a short intro is good.
The Guy who co wrote a song ,then told us the story of the song,why he wrote the song,then the words of the song ,then sang the bloody song ,then told us about the song again.
Doesn't get my vote.
Neither does the guy who turns his gig into a lecture about ....zzzzzzzz.
It is nice to know the title + who wrote it if known.