Ben Hallert wrote:
How? If they have to rely on primary radar alone, then how could they
reasonably be sure they were watching the plane they thought they were?

Ron Natalie wrote:
By watching the blip. I've flown into Dulles with only a receiver
and primary radar return (turns for identification and to indicate
our intents). I've also departed Dulles with comms but with no
transponder while the primary radar is out. ATC can be resourceful
when they have to be.

Not in the last year, was it! :-))
I thought the Governor of KY was the last to receive that service.