Remove an unused length

What is the point of introducing a new length without using it? Is it for some debug output or something?

liuthesis.cls

@@ -373,12 +373,6 @@
 \RequirePackage{calc}
 \RequirePackage{ragged2e}
 
-\newlength{\marginboxlength} 
-\setlength{\marginboxlength}{\paperwidth} 
-\addtolength{\marginboxlength}{-\textwidth}
-\addtolength{\marginboxlength}{-\spinemargin}
-\addtolength{\marginboxlength}{-2mm}
-
 \definecolor{nicered}{rgb}{.647,.129,.149} 
 \newsavebox{\feline@article} 
 \newcommand\feline@article@marker[1][4cm]{%