5-in-50,
In reality, there was no risk to mitigate.
In reality, as opposed to the history of aviation medical so called "standards", there has been little understanding of real, as opposed to imagined risks.
Don't forget that these so called medical standards arose from air force aircrew medical standards, which were imposed to exclude most candidates, not include.
As with colour perception standards, Australia pioneered the use of "drivers License" medical standards via the AUF, now Recreational Aviation Australia, with something north of 10,000 pilots and absolutely no evidence, over 25 plus years, of medically related increased risk, either to pilots themselves, their passengers, or those on the ground.
After all, 100% of pilots medically self certify before flying, except for one day a year, the day of the medical.
Having pioneered the driver's license medical, it's introduction more widely via a CASA "standard" was always going to be a stuff up, it never was a driver's license medical at all, and the medical and operational restrictions have no basis in reality, they are no more than what could be achieved by the proponents within CASA against concerted opposition.
Australia having pioneered the driver license medical standard, it is very sad to see Australia dropping behind our aviation peers, as genuine driver's license medical standards, following Australia's original example, are introduced elsewhere.
Instead, what do we have here -- a completely unjustified "tightening up" across the board, in the name of what?? There is no evidence that medical standards pre. Dr. Navathe were an aviation risk (or "unsafe", if you prefer the "safe" word), and justified what has happened.
Rule by law!!
Tootle pip!!
PS: A mate of mine has just told me that the biggest reason for loss of license right now is diabetes, not because of an epidemic of the disease amongst airline pilots, but because CASA has changed the definition of diabetes.