This rings true to me and I like it a lot.
It's important for employees (especially the skilled, self confident kind) to remember that outside of their current job, boss and co-workers, no one knows who they are, what they've done, what they can do. The default opinion is that they are average until proven otherwise.
Anything you can do to prove otherwise (that you're not average or mediocre) is a win. Anything at all.