[weblacky]

Erasing drives isn't necessary, unless you are concerned with data security. Simply doing a mkfs will destroy the existing filesystem and replace it with a new one.

It's been my personal experience unless you're also going clear the volume header you still could run into issues attempting to reload a drive that was previously set up with Irix.

if you're reinstalling the exact same version over and over again I would agree with you that things should probably be fine just learning how to do a mkfs at the inst before you open media.

But a lot of new people start getting antsy and they start switching distribution discs or overlays because they think they're corrupt or doing something wrong and then they start merging files into one another. Instead of going through the nuance of training people which of their file systems they can reformat and how to use the volume management tool to erase the miniroot files and all that so it's cleared it's a lot easier from a procedural standpoint to tell them to just erase/blank the entire drive properly to start from scratch and learn how to go through it correctly, by repetition.