National Australia Bank’s new chief executive, Andrew Thorburn,has made important changes in the management reshuffle that marks his first day in the driver's seat, but the roles of several key executives have been confirmed, and Thorburn has effectively endorsed the management structure he inherited from outgoing CEO Cameron Clyne.

The key departures are group executive business banking Joseph Healy, and group executive enterprise services and transformation Lisa Gray.

Healy has been replaced by Angela Mentis, who worked for him as executive manager of nabBusiness, the small and medium enterprise lending unit that sits at the heart of NAB's business banking franchise.

The group's business banking division boosted its market share from 19.4 per cent in December 2008 to 24.7 per cent in November 2012 after swimming against the tide during the global crisis and continuing to lend when its competitors were retreating. It’s given back some of that gain more recently, but still controls a healthy 22.8 per cent of the market.

Business loan demand is still subdued and competition is intensifying, but the change at the top of the division suggests Thorburn is determined to maintain business banking as a NAB specialty.

He also obviously wants to stay in the top job a long time – he has reportedly told staff that 10 years is the aspirational target – and has created a team he thinks can go the the distance with him.

Healy will take a six-month sabbatical to lecture on banking and finance and study Mandarin and Chinese culture at a university south of Shanghai. Gray wants to lead a company eventually; with Thorburn in the role at NAB and in place for several years if he performs, she will pursue that ambition elsewhere.

Thorburn moved quickly to get the changes in place on his first day in the CEO job. The new management team reported for work on Friday at 7.30am. He and his direct reports know the reshuffle is also significant for changes that haven’t been made, however.

Gavin Slater has been confirmed by Thorburn as the head of NAB's big personal banking division, which built mortgage market share under Clyne’s leadership by undercutting the big banks on lending rates, and also cutting bank fees.

The bank grew housing lending at 1.07 times system growth in June, and was the only one of banking's big four to record above-system growth. It has posted 19 consecutive quarters of above-system housing loan growth, and has raised its home lending share from a parlous 12.8 per cent in March 2009 to 15.4 per cent.

Fee cuts and aggressive variable home loan interest rates cost NAB about $300 million in their first year of implementation, split equally between fee cuts and rate reductions. New revenue came in as NAB gained market share, however, and the personal banking division’s earnings grew by 65 per cent from $743 million to $1.23 billion between 2009-10 and the year to September last year.

Craig Drummond, a key hiring of Clyne’s, has also been confirmed as the group’s top finance officer and strategy co-ordinator, and Andrew Hagger has been confirmed as the boss of NAB’s wealth division, including MLC.

NAB’s competitor CBA is at the centre of this year's storm over conflicted and incompetent financial advice, but Hagger is still in a hot seat. The Murray inquiry is looking hard at the entire superannuation sector, and at problems that many believe are magnified by bank ownership and marketing of wealth management services.

In summary, this is a middleweight restructure by NAB's new boss. Some divisional leadership roles have changed, some have not, and the divisions themselves are unchanged. The organisational structure that Cameron Clyne presided over has been implicitly endorsed by his successor.

Sharemarket correction needed

The sharemarket could actually use a correction that refreshes, but I am not sure that the 2 per cent hit that Wall Street took on Thursday night and the fall on markets west of Wall Street including our ASX is the beginning of it.

Triggers for the fall included Argentina's debt default, concern that Portugal's Banco Espirito Santo will need to be rescued after posting a €3.6 billion ($5.2 billion) six-month loss, continued geopolitical tensions (Ukraine, Gaza, Iraq) and, of course, the ever-present risk that investors will pull on stage two of last year's "taper tantrum" when they decide that they know when US interest rates will rise.

The list is a bit too long, though. Viewed as a collection of concerns it is enough to warrant a sell-down, but the individual issues don't seem capable at this stage of turning a selloff into a fully-fledged correction.

Portugal and Argentina are not as important to the markets as, say, Spain or Italy, previous focuses of bank default and sovereign default speculation.

After the rise of China and Asia, Argentina is a much smaller piece of the global market than it was when it defaulted in 2001.

It was one of the founder members of the MSCI emerging market index in 1998. These days, it is in MSCI's "frontier" market index, alongside countries such as Pakistan, Mauritius, Ukraine and Bulgaria.

Over in the US, rate rises will bear down on share and bond prices initially, and the expected mid-2015 timing of the first US rate rise has certainly not been extended by this week's news that the US economy grew at a 4 per cent annual rate in the June quarter.

Rates are only going to go up when the US economy can withstand it, however. Rate rises when they happen will be part of the post-global crisis recovery story.

The Maiden family owns NAB shares.