Thanks to some excitable types in Canada, BHP Billiton’s potash ambitions and the pace of expenditure on its Jansen project beneath Saskatchewan’s prairie got undue attention in the March quarter production report.

BHP shaving $US200m off the annual spend on its go-slow development of Jansen is neither here nor there for a project that it has long been said won’t hit its straps until well in to the 2020s.

And for the record, BHP is not about to revisit the notion of busting open the industry by having another $US40 billion tilt at Canada’s national champion in the industry, Potash Corp. Arrant nonsense it is.

The 5 million tonne lift in 2014 production guidance for iron ore was more significant than all of that from an earnings perspective. A dry wet season and the ramping up of the Jimblebar was the simple explanation.

But again, there was a more interesting figure disclosed in the quarterly report, and that was the round-about disclosure that development expenditure in the onshore US oil and gas business was running some $US400m over budget.

BHP reported that at the nine-month mark of the year, it had pumped $US3.4bn in to the onshore US business and that expenditure in the March quarter alone was $US1bn. No drama there, was the message from BHP, because the March quarter was “in-line with our planned annual investment program of approximately $US4bn.’’

But with at least another $US1bn to be spent in the June quarter, expenditure of $US4.4bn for the full year is not approximately $US4bn. Given that potash is under the care of BHP petroleum chief Tim Cutt in Houston, the slowdown in the pace of investment in Jansen can now be seen in another light.

Now just because Cutt has been spending at a rate of more than the $US4bn like he said he would — most recently in December’s investor petroleum briefings — does not mean that there is anything wrong in busting the budget now and then. The end prize is what counts.

The massive annual spend in the onshore shale business is all about creating a business that it has previously been said will become self-funding in 2016 before generating some $US3bn in free cash flow in 2020, and beyond.

And a clear message from that December briefing was that push in to US onshore had the highest returns and shortest payback compared with just about everything else BHP could invest in. Come 2017, it will be pumping out 500,000 barrels of oil equivalent on a daily basis, of which 200,000 barrels-a-day will be the higher revenue generating liquids production.

BHP just needs to more upfront about the cost of getting there.