Hello -
Typically I like to propose at "forecasting by exception" strategy to large-scale automatic forecasting users:
automate as much as possible, come up with a smart way to detect exceptional cases (like rules on reasonable accuracy levels) or series which are of major importance to your business, and deal with those in an interactive manner.
In a way a large scale forecasting system should behave like an autopilot on a plane: it should handle "ordinary" cases well - but of course we are all more than happy that pilots are still in charge of the plane, who can interfere and address "extraordinary" cases.
In fact this is one of the design principles which we have in mind as we are building the next generation of SAS Forecast Server.
Please feel free to have a look at our ideas here: Analytics 2013 - Day 1 - SAS Presents - Udo Sglavo - YouTube.
Thanks,
Udo