Hi Danger. My understanding of this rule comes from personal experience (and you'll find it clearly stated in the rules)
The final legs of my J 280k trip next June involve ADL-DRW (STOP) DRW-ADL-MEL. The ADL-MEL leg is the next day as I can't make the final ADL - MEL flight in time afyer getting in from DRW.
I had this itinerary ticketted fine once, but it was pulled up by QF after I phoned through a second round of changes to other legs of the itinerary (no doubt a smart cookie in the ticketting dept picked up on it), and deemed to be invalid as it was taking my trip to 6 stops - they were very firm on the fact that a domestic transit must be same day - the number of hours (whether 16 or 3) doesn't come into it.
After several weeks of negotiating (and concern about the unticketted state of my ticket!), a kind supevisor in the call centre reticketed it and allowed me to leave the original flights in, presumably as it had already been ticketted. Interestingly, I found that very few QF staff were aware of the different rules between domestic and Intl stopovers - so it's possible that you might get lucky, but don't count on it.