Constant Content

For authors who also post entire articles in the long summary, do you think it's safe to do so for a public request from someone with a zero purchase rating?

I wouldn't have a problem with it. Zero purchase rating just means the customer is new and hasn't bought an article yet. It doesn't indicate that the customer is out to steal content. The customer will have three days to view the article exclusively before the article goes to the general pool. When that happens, if you're more comfortable with excerpts, you can go back and edit the long summary.