The Jerwoods kept the winners honest to finish runners up with Englishman Charles Apthorp and Irishman Alan Green third.
"I think it was really shifty so I just think we were quite lucky because the wind was shifting all over," Harper said, saluting the race officials for ensuring proceedings were under way with timely decisions for a start in the third attempt in 7-10 knot winds.
The shifty nor'easterlies or easterlies were whipping up swirls that would have left even the Manawatu Gorge windfarms in knots.
"There's always a bit to look in it so we just happen to get through the first leg of the course nicely, adapt to things and manage it well," he said.
However, despite the nous of 64-year-old Goacher, who is on his 12th world champs and has three crowns to show off, his crewman attributed yesterday's success to luck.
"Greg Wells had a new pair of shoes on today and they [crewman Richard Rigg] did well today," a chuckling Harper said of fellow Britons who are steering Agatha and sit 10th overall provisionally after finishing fourth yesterday.
But that banter between the Poms extends to the Ockers as well.
On a marginally serious note, Harper suspected he and Goacher performed their "separate bits quite well".
"We just keep doing things properly and consistently. I don't think we did anything special," he said, as the pair lapped up the balmy Bay weather.
The boatbuilder from Southport, between Liverpool and Preston, said Goacher's experience from similar shifty conditions in Windermere Lake was godsend.
"It's a renowned lake where the wind is everywhere."
While he and Goacher started sailing in 1991 they didn't pair up until two years ago although the crewman has yet to etch his name on the silverware.
No doubt he is hoping a bit of sailmaker Goacher's magic will rub off on him today for his maiden title.
"I think there's only one other boat that can push us," Harper said, referring to the Jerwoods. "They managed to get past us [on Wednesday] which was annoying."
Harper started sailing when he was about 4 years old with his father who just enjoyed run-of-the-mill boats.
His flirtation with Flying Fifteen came almost by accident when he was holidaying as a 23-year-old and bumped into a gregarious bunch of sailors.
Building and repairing any type of boats followed his love of sailing.
It is Harper's first visit to New Zealand and the Bay and its people have struck a chord with him.
"It's a lovely place but I wish I had a little bit more time to go around to have a look."
Regrettably Harper has to make it back home in quick time because work is piling up.
"I think there's a whole host of us in the plane on Saturday [tomorrow] morning."
Today Harper said he and Goacher would take the attitude of winning the last race rather than playing a conservative card.
Canberra sailors Matthew Owen and Andrew Reed had a day to forget finishing 25th, their discard, but retained their third overall status on 34 points.
Napier club pair of Hayden Percy and Scott Pedersen, on Fflorin, are fourth overall on equal 39 but remarkably on an older vessel compared with the more modern species most of the gun sailors are using.
British pair David McKee and Mal Hartland are on equal 39 with another Kiwi combination of Murray Gilbert and Jonathan Burgess.
Apthorp and Green follow, on Foof, and are on 40 points with Hong Kong flag fliers Ashley Smith/Adam Kingston on 44.
