You could almost suggest that there is little use for red flag warnings in the form in which they are used these days. Falling limbs, steep terrain, ants, snakes, loose rocks on burnt ground and most of your other everday uses for red flag warnings come down to the basic use of your eyes. If you went to a rural job, depending on the terrain, wouldn't you expect ALL of these things?
Its the things like a change in weather, a strong shift in wind, a gully wind starting up in a peculiar direction, a section of road/track collapsing or becoming impassable that really warrant a Red Flag warning.