I work as a mechanical engineer, in the building industry (HVAC) and while this is also quite normal, the word that gets thrown around is variation, obviously to the contract.
Reading the article, particularly between the lines, it appears that the problem wasn't really with the studio; they were trying to get more money out of MS, but MS just decided to kill the project rather than have a cost blowout. While mission creep did kill the game, the studio didn't plan any contingency or mitigation for a cancellation (or more likely it was just sack everyone).
Maybe if those links supported what you're saying, I could argue. Problem is firearm homicides and firearm suicides in Australia definitely did not peak in 1996/1997, as they had been trending downwards since the mid 1980's. The only thing is that 1996 had a big peak due to the Port Arthur massacre, but even then, more people were killed by firearms in 1992 than 1996. firearm homicides had been trending downwards since about the 1980's and there's no structural break to signify a change as a result of the buyback legislation. Similarly applies to firearm suicides.
Owning weapons is a common law right, however statute has the power to override and essentially revoke common law rights. As a result, we have no guaranteed rights in Australia (because our constitutions don't define any, except for free political speech and a right to vote, no those are the only two protected in our constitutions), because the parliament can just change it immediately.
So now we're seeing our democratically elected representatives debate, adjust, and they will pass laws regarding metadata retention. Is this a situation of the people speaking? Can you really suggest that metadata retention is something that the Australian public really want? Both sides of politics are agreeing to metadata retention in principle, so it's going to happen.
Anything free is worth what you pay for it.