Author failing to populate author if feed author doesn't exist...

We've been noticing on a lot of blogs that if you choose "use feed author" for the "Set author for new posts" option, the "If author in feed does not exist locally use" option will not use a local author, instead posts will get published with no author ..... choosing a local author in the "set author for new posts" solves the issue...... In other words, the default option to choose a local author if feed author does not exist is only working very sporadically .... just a heads up.