I think it's a matter of doing the right thing vs. the need to
use it... a good habit to get into.

habit? Which habit? It's a tool, which we use when needed. A good habit is to
practicing nav skills. Leaving the cover off the compass 24/7 has nothing to do
with that. I doubt Suzanne will have trouble reading the compass after it's
been covered for the day.
Again: No reason to have instruments exposed when not in use. Sun kills.

RB