@prsguy, I think we're thinking the same end result.
I don't believe we'd encounter any conflicts in scheduling logic. Since the MV is a global device setting, it will always be on anytime a schedule is running (or off if no schedules are running).
Please see the diagrams below. A green circle indicates a valve is on, black line indicates there's no water available, and a blue line indicates water is flowing (or available to flow):
ON (MV enabled and Z1 running)
OFF (MV enabled and no zones running)
Application to your system:
If you had a lawn schedule set to run from 5a-7a, then the MV would turn on with each zone valve. The hose bibs would pressurized the entire time from 5a-7a.
If you setup a fake hose bib on an unused zone terminal, the schedule to run from 8a-6p, the MV would turn on to pressurize the hose bibs during said time, but no water would be used unless a hose bib was turned.
Hopefully this helps to clarify the system status between MV and zone activity.