Heston... Whilst you maybe correct do do you not think the original poster deserves some credit for exercising sound airmanship. If the majority of GA had any idea of the manoeuvring jets do inbound and outbound of a MATZ they'd avoid it by at least 10nm! (clearly not always practical) but if you are going within say 20nm please call them. We far rather hear from you than not. I fly a fast jet with TCAS and it's certainly helps but has major flaws operating in such a dynamic environment. It certainly can't be relied upon to save the day.
We had a paraglider the other day that decided to fly at 1500' 2.5nm round the zone sightseeing. He did a complete 360 of the zone at about 1000am. Two instrument approaches broken off, one aborted practice engine failure after take off (after a very late visual spot) and I had to manoeuvre my 3 ship in close formation quite aggressively to avoid smearing the chap all over us. Legal - yes. Sensible - you decide.