Steady on CUJ! The 'controller in question' was using the equipment in a perfectly acceptable manner and in the way it was designed at the time. Unfortunately this led to confusion of the targets and the subsequent incident. Whether the equipment should have been designed in the first place not to allow this to happen is a valid discussion.
The SI/OPNOT or whatever it was that appeared on the sectors telling us not to move TDBs without a leader line was AFTER this incident (the stable door banging shut with the sound of the horse's hooves receding into the distance..
..).
Don't pillory the guy who made a mistake with the inference that he was acting incorrectly.