With one or two exceptions, most good songwriters usually have "other strings to their bow" so to speak. At least until they have "honed" their craft.

I don't think the majority of us would really mind too much if somebody went up and sang one or two of their own songs even if they were still finding their way. We would be polite enough to listen and, if it was really bad, go to the loo as has been suggested. Of course, if we had a succession of mediocre singer song writers in the same evening it might be a different matter.

So floor spots or even short sets aren't the issue. However, it's unlikely that I'd want to sit and listen to somebody for an entire evening, e.g. two 45 minute sets if it was entirely self penend material and he or she was still learning their craft.

The best writers will surely be aware of and respect the work of others and will learn much from acknowledging good songs written by others whether recent or traditional. After all, even The Beatles performed loads of covers in their early days.

Sometimes, I can't help but get the impression that some singer songwriters have never listened to anyone else other than themselves.