OK, based on almost thirty years working in ATC and ten more for an airline (and nearly 2,000 hours private flying), it's a situation based on a combination of experience and confidance.
When operational, if I was unconfortable with a particular situation, I would ask if (my) intended flight path for that particular aircraft was aceptable.
When (rarely, thank god) I found my sphincter muscle bouncing between sixpence and half-a-crown I would give an instruction - occasionally in fairly forcefull terms - to resolve the situation.
I offer no apologies for these actions - I would much farther be criticised by the pilot afterwards than receive an "invitation" to their funeral.
Les.
Last edited by aviosaurus; 5th Feb 2007 at 20:01.
Reason: typing in English on an AZERTY keyboard