Jack
The real answer to this question would lie in a review of the incidents of altitude infringements on RWY 34. The search function on the ATSB website is completely inadequate for anyone external to do this research. With the current state of the ATSB, I doubt you'll ever get the full information required for a proper decision. However, with only an hour or so's work I turned up with 6 instances in the last year or so.
Considering the Thai flight, they could have easily landed with a mild cross wind on RWY 27 with ILS. I presume (note: presume because the ATSB did not consider this) that the aircraft was directed to RWY 34 for ATC operational reasons and not aircraft or weather requirements. Some degree of understanding about this would help inform the assessment.
I fly twins not jets. This approach would be pretty easy in the twin. However, my 747 captain mate says it is not as simple in a widebody jet and even less simple in a glass cockpit wide body jet. Something to do with the flight control system that I don't understand. It seems to me that the most critical group of flights on this approach are therefore foreign long haul, glass cockpit widebody jets (none of whom are participating in this discussion). How welcoming do we want to be to overseas guests?
My understanding (which is imperfect) is that GPS has not made nearly the inroads to airlines that it has to GA. I understand that where it is used in airlines it typically feeds into the INS system to update it, rather than being used as a standalone system. I think it will be many years before we see airliners using GPS RNAV approaches. And unless Australia gets WAAS it may be never.
The truth is that we have under funded aviation infrastructure for years. In Australia we get by because we have better weather than most of the world, lower traffic densities, possibly better pilots and better controllers
. There comes a time when we just have to do whats right. Surely at least Sydney & Melbourne should be at a similar standard to Singapore, Hong Kong, Bangkok, Heathrow, Los Angeles, Frankfurt, etc.
The maritime industry gets new lighthouses, marine GPS WAAS, channel dredging, port upgrades and other infrastructure without industry funding. The trucking industry gets free use of roads, B-double assembly areas, emergency repose (police, ambulance, etc) without any significant industry contribution. Its only aviation where we get hung about about user pays. And before someone mentions Dick Smith - it started in the seventies with Frank Crean.
The rest of the world is investing in WAAS, ADSB-in traffic, radio weather, autoland and we're trying figure out if we should fully adopt ILS.