Buchanan has gone about rejigging things since starting his four-year contract, which runs through to 2015.
Among them, he disbanded the old three-man selection system in favour of having the head coach and a national selection manager do the job. That person is another Australian, a former lawn bowls administrator, Kim Littlejohn.
On his relationship with Buchanan yesterday, Wright quipped - only half in humour - that "it's fair to say we're probably more comfortable coaching against each other, which we did for 4 years [than working together]".
It is likely that NZC, in offering Wright the chance to continue, said the arrangements with Buchanan would remain in place. That would have helped Wright make up his mind to pack his bags after the West Indies tour in July-August, which completes his contract.
There were other factors. Cricket is a 12-month merry-go-round. It takes a physical toll on more than just the players.
That grind was probably a factor in the 57-year-old Wright's thinking.
When Wright finally got the New Zealand job at the end of 2010, the popular view was "about time". He spoke yesterday of the support he had received and he is a popular figure. With those supporters, yesterday's developments will have gone down as well as a bucketload of bouncers on a dodgy pitch.
The players enjoy his company. But, from Wright's perspective, if he felt his hands were being tied, his approach compromised by his boss, then he could not continue on that basis.
You hope he won't be lost to the game. He is a good cricket man, whose heart, in terms of New Zealand cricket's welfare, is in the right place.
You can also be sure that the person who replaces him will be on the same wavelength as Buchanan.
For at least the next three years, New Zealand Cricket can't afford it to be any other way.
