"The way I train for this exact situation is to turn my strong side away from the threat and get my hand on the firearm. Not drawn yet. If the person makes a hinky, furtive move of some sort, I can draw and hold it behind my leg, pointed downward."
Most aspects of this have been covered so I will limit my comments to the above. I also like and use the above. It has been my experience my self and working with others that the clearing of the garment and obtaining a grip on your gun generally reduces draw/first shot times by around fifty per cent. In addition to preparation for a response the turning action shields your weapon from view thereby eliminating brandishing claims.