Leave Debug on in Django for internal application
The Django docs warn to never deploy with debug on:

Never deploy a site into production with DEBUG turned on.
Did you catch that? NEVER deploy a site into production with DEBUG turned on.

Later, they give a reason that isn't related to security:

It is also important to remember that when running with DEBUG turned on, Django will remember every SQL query it executes. This is useful when you’re debugging, but it’ll rapidly consume memory on a production server.
I'm working on a Django project that I took over for someone else that is only used internally.  It's not deployed to a website and can only be accessed on a local network.  The previous developer had left DEBUG = True in settings.py.  Django docs really emphasize that leaving DEBUG=True when the site is in production is bad.  The site is inaccessible by anyone not on the local network, and is only even looked at by ~5 people regularly.  Aside from security reasons, is there any other downside to operating permanently in DEBUG mode?