Personally, I don't enjoy trying to figure out a tune on the cuff. Have I done it? Yes, but I hate it...Sometimes its even worked out fine, but I still hate it...
To try and manage my way through a song I don't know, not to mention coming up with some lyrics is something I try to avoid.
I'd usually just say, I don't know it...but I can play something else by that artist, or something from a similar era, etc.
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Bill in Dayton
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Bill in Dayton