Yep! Guilty - over thinking.
LIke I mentioned, had seen a site such as described ... K12 - elem, intermediate, jh, and a hs. Lesser used elem and Intermediate campuses.
Once admin got them all to a version, that's where they stayed the remainder of that academic year. No look-sees at themes nor plugins. Now I know I've never seen a '0 day flaw' officially announced concerning Moodle code but did see one about libraries used by Moodle code the other day. Personally, I get nervous if not running supported anything.
Is there any official Moodle docs that describe how to set one code base, one DB, for multiple sites ... URL please.
And one of these days, I'll learn not to respond in developers! :| ... just 'lurk' in learning mode.
'SoS', Ken