Thank you all for your comments. I do dry mount my prints (on acid-free foam board), and overlap the print border with the mat. It is the print border that shows and not the backing board. Perhaps with glossy prints I can change that practice.
What is the importance of having the signature show on the front?
"Make good art!"
- Neil Gaiman
"...the heart and mind are the true lens of the camera".
- Yousuf Karsh
"We are what we repeatedly do. Excellence, then, is not an act, but a habit".