David Gerard wrote:
Every time I hit an article without references, sources or even external links listed, I put an unref tag on it.
That's long been my habit too, but I've actually started skipping that in some cases now that I've had some unpleasant experiences with articles going up for deletion on the basis of WP:RS. If the article looks reasonable enough to me but hard to reference within a five-day deadline I don't consider it worth the risk.
I still do {{citation needed}} when I hit statements that seem dubious, though, since that seems less likely to bring ruin on the article as a whole.