On the plus side, Wanganui's lineout strengthened, particularly when reserve hooker Roman Tutauha made his return for his blazer game, and the rolling maul remains unmatched - retaining structure throughout.
While predictable, driving strength is Wanganui's go-to attack and created hooker Karl Parker's opening try and the crucial penalty try in the 65th minute as Horowhenua-Kapiti desperately tried to collapse the maul at their line.
In a big call, coach Karl Hoskin "rolled the dice" by moving teenage winger Zyon Hekenui into first-five for Areta Lama early in the second half.
While some of Hekenui's clearances were shallow, he held his own under tremendous pressure, while halfback Lindsay Horrocks redeemed a middling first half by hustling Horowhenua-Kapiti non-stop for the next 40 minutes.
Prop Shaun McDonough can also hold his head high after an inspired match.
In such a close contest, the officials were in the spotlight as referee John Dustow sent Horowhenua-Kapiti prop Aaron Kearney and Wanganui lock Nick Cranston to the bin at different times for rough play, while a possible second half try to Wanganui fullback Jason Temara was called back late by the linesman for a foot in touch.
Walking off the domain blessing the five points, captain Peter Rowe remained at a loss to explain his team's Jekyll and Hyde nature.
"If we lifted tempo a little bit [we'd be fine], but it's the same thing that's happened for a couple of weeks.
"It's frustrating, I don't know what it is.
"The fitness is there, it's a concentration thing."
Hoskin agreed the team should be putting phases together but they keep coming from behind the eight-ball before they do it.
"It wasn't a pretty game. We're fitter than teams, but our minds just wander.
"I'm not overly happy, but we live again."
A dropped kickoff saw Horowhenua-Kapiti nearly score in the opening exchanges as wingers David Thompson and Etuale Togia went close on either sideline.
The home team's flanker Casey Watson asserted himself, while fullback Michael Tambour was dangerous every time he got the ball at pace - which was often.
Led by Rowe, Wanganui's pack remained composed and mauled their way to the line to put Parker over, Hekenui converting from the sideline after 17 minutes.
But Wanganui were immediately on the back-foot as Horowhenua-Kapiti claimed the kickoff and earned a 45m penalty, which first-five Adrian Curry nailed.
After nearly breaking through twice before the final pass slipped from hand, Horowhenua-Kapiti finally crossed with Tambour feeding Togia for the converted try in the 27th minute. In reply, Wanganui's backs just shuffled the ball along with winger Sailosi Naqiso easily bundled out on the end of it.
It must be a matter of communication because only minutes later from broken play, those same backs uncorked Wanganui's best try of the year.
A Temara-led burst was turned over and kicked away but Naqiso regathered in midfield and sliced through, as Parker and then Doug Horrocks found Hekenui to dash away under the posts.
Wanganui would have been confident with Kearney binned on halftime, but right after the resumption they were torn open as Tambour and Togia spread the ball and second-five Luke Harvey outstripped the cover defence to the line.
The numbers' advantage reversed with Cranston binned and then Thompson made mugs of the entire Wanganui backline as he stepped through four woeful tackle attempts to score, 24-14 with 23 minutes left.
Upon Cranston's return, Wanganui worked for position and after lock Sonny Woodmass claimed a lineout, his forwards drove him to the line where Dustow spotted Horowhenua-Kapiti's infringement, jogging to the posts.
Finally, firing on all cylinders, Wanganui got straight back on attack as Temara, centre Ace Malo and Naqiso all combined out wide for Temara to dive over, only for the linesman to decide late that Naqiso stepped out two passes back.
Horowhenua-Kapiti fumbled the lineout and from a 10m scrum, Wanganui spread and Malo crossed untouched, reserve second-five Soonalote Tauailoto adding the extras with 11 minutes left.
Horowhenua-Kapiti's helter-skelter backline remained a threat, but turnover and penalties combined to sink their chances of a famous upset.