The dog's audible warning can trigger a human response varying from a freeze up or a quick decision to run.
The key similarity is the primal communication that is displayed between the two,on a competition field or inside a junkyard.
A person unfamiliar with dogs,would not be able to readily discern either dogs intent(your aforementioned difference)
by the by,,did you watch the vid of the 'untrained dog ' posted here?
E-Dog - 2012 WPBTCA National Championships
The time when screech owls and Bandogges howl and spirits walk and ghosts break up their graves.
Act I, Scene IV of William Shakespeare's "King Henry VI"