And they had needed to speak so they could get 5 miles deconfliction on a CAT aircraft which you could see anway and would be deemed seperated from in CAS but under ASTOCAS you would be vectored away from.
If you don't get a useful service why bother speaking to a unit?
The controller does not know that an unknown aircraft has "his" aircraft in sight and has to be constantly alert that it might change height and track and compromise the deconfliction distance (which, with the agreement of the other pilot, if in contact, could be reduced to 3nm or 1000ft). (Given the same circumstances in CAS, there would be no "deemed" separation as such, but avoiding action and an attempt to stay 5 nm away from the unknown traffic).
And I've certainly heard the occasional air trafficer throw their teddy out of the cot when it happened.
Sorry that you view it in terms of "teddies and cots". Look on it as an understandable frustration at the occasional habit that can be hazardous for
other pilots, not
just for the controller's (not air trafficer, or even trafficker) blood pressure!
2 s