Here's the "before" photo.
And here's the "after" photo.
While it doesn't look significantly different, the hairdresser told me she took off 1-1/4 inches of hair (since I'd not been in for over 1-1/2 months). The key is that most of the hair that gets cut off is on the sides and the back. There's just no other hair to cut off, as you can clearly see. (And no, the beard stays!)