Claire Trevett: Chris Luxon's pick of Simon Bridges as his number 3 was more than just an olive branch

Simon Bridges was not only the obvious choice for new National Party leader Chris Luxon to give the finance portfolio to, it was the critical first move for Luxon.

It did not all go to plan – rather than drag Bridges to Parliament, Luxon travelled to Tauranga to make the announcement alongside him in between a greengrocer and a butcher. It was to be a big moment for his new "unity" show.

Bridges has stayed out of the public eye since the day he withdrew from the leadership contest and conceded to Luxon.

But an hour before they were to meet in front of the cameras to announce Bridges' appointment at number 3, Bridges' son came a cropper off a swing and ended up in hospital.

Luxon turned up alone – although Bridges did take the precaution of texting some media in advance so they did not think he was standing Luxon up without good reason.

The chance to get those first symbolic photos together was lost, but the intent was clear.

While normally reshuffle announcements are all made together, Luxon opted to announce Bridges' appointment early.

It was not only to show the two men had put any rancour from the last week behind them and reached an accord.

It was to start off with images of a potential future Prime Minister and finance minister side by side.

In Government, the relationship between a Prime Minister and a finance minister is more critical than that of PM and deputy. Finance ministers have a lot of influence, and it is partly why the deputy is often also the finance minister. That makes it also important in Opposition.

Helen Clark and Michael Cullen, John Key and Bill English, and now Jacinda Ardern and Grant Robertson were all formidable pairings. Luxon is clearly hoping to follow in their footsteps.

It is an important move in starting to restore National's credibility with voters.

Luxon denied he had come to an agreement with Bridges in advance but there was undoubtedly an element of bridge-building to it – as there had been with Clark and Cullen and Key and English when they first paired up.

But it was not all about that.

Luxon is over-optimistic in his assurance that people will consider that every single person in his team would be a better minister than their counterpart on the other side.

But Bridges is definitely the best person for the finance job. It will be a key area for National over the next two years as it tries to capitalise on the weakening support for the Government.

In Opposition, it requires a mix of political attack, strategy and competence. Bridges is a much more even match for Finance Minister Grant Robertson than his predecessor Andrew Bayly was.

Crucially, Bridges will lend his own political experience to Luxon, who has little. Luxon showed that in his announcement, incorrectly saying Bridges is chair of the finance and expenditure committee (he is not, but was once), and only highlighting Bridges' role as transport minister. He held other relevant portfolios as a minister, including economic development, energy and associate finance.

When Bridges was leader, he knew how to get under Prime Minister Jacinda Ardern's skin. Luxon will have a different style, but it won't hurt him to have Bridges there when things need to be rarked up.