I agree with what you say about them seldom being for the better, but why would they revisit? I don't see what the difference would be between someone traveling from the US to Delhi via Hong Kong versus via Chicago.

An AONE3 from Oz has always been possible, just not sold except as a circle pacific. From South America it's not possible.

An AONE2 is by definition a round trip.

The changes that youre thinking of would be going against the core of the fare itself. In other words, it would destroy it. I can't see any of that happening, to be honest. If they were going to destroy the fare, it would have happened by now. No excuses are really needed.