Does the CVR starts with oil pressure on engine start?, hence letting it fall unaided on push back makes no difference at all as the oil pressure is zero before start and then CVR is not recording. All sounds a bit odd to me. On the Airbus it's a turn switch with no pressure. so that's another myth busted!
We state " Parking brake released" rather than depend on some woolly interpretation of what the aircraft status may be, having said that, I can imagine one would get distracted in the enthusiasm and excitement of creeping forward to the holding point at 27R!
