Sing, sing by all means. And change when you think you should. I guess it's the political aspect of certain songs that concerns me. What if somebody did a version of Woody's "Deportees" that made it sound like blowing them up in an airplane was a swell idea. That would strike me as wrong somehow. As for nonpolitical songs, I change 'em all the time; it's one of my specialties.

Chet