Antique Torrey Paddle Strop

[INDENT] Yesterday I picked up an antique Torrey Paddle strop. It has various types of leather on three sides. The fourth side seems to have a painted surface that is mostly worn away to the underlying wood. Directions on the cardboard sleeve state "using the hone only when the razor is very dull''.... and to "place strop in case hone side up". The cardboard sleeve fits the strop very snugly. There is no room for any missing hone. Could the "painted side" have been an abrasive paint used as a honing surface?