Even if a collector did not want to use the andiron, one does not display as well as two.
From the kansas.com
Andiron is a well-bred son of A.P. Indy who woke up last time out and broke his maiden in impressive fashion.
From the kentucky.com
Would one andiron be worth half as much as a pair?
From the kansas.com
Kind of like yellow lights going off on the andiron, under lean production, indicating that the system is stressed just enough to be operating at maximum efficiency.