I would like to add this to the mix, remove the Dar Bars, and replace them with a 'Sighting' report of what is there, Alt, heading are they outbound, or RTB, then as they move from one sector to the next, a 2nd sighting would be needed to keep track of them, in WWII, a large bomber force could fly a long distance and not be seen till it reached the target base!.
Keep this in mind, and planes upping from a TG would not bee seen unless the ENY was there or in a position to spot, like the 'Coast Watchers', that would give a here of there mark to follow.
And as several have pointed out, the total # of radars were few and not real good, fooled by dropping aluminum strips and small scraps on metal, just ONE plane could make the ENY put every AC they had and not see a thing, then the next time they sat on the ground when it was the real thing!
1WILDCAT over/out