Wests Tigers enforcer Martin Taupau can fly pretty close to that line between aggression and madness sometimes, as witnessed in the Kiwis' historic win over the Kangaroos last weekend, but his teammates wouldn't have him any other way.
Taupau was in the thick of things on Sunday against the Aussies; his immediate impact off the bench was crucial to New Zealand's win and he was close to best on field.
His 129 metres from 12 powerful charges was the most of any NZ forward while his four tackle breaks was the most of any forward in the match and he added two offloads and 13 stinging tackles.
Despite his quality all-round performance it was a throat-slitting gesture he made to Kangaroos back-rower Sam Thaiday for a crusher tackle (albeit one that is likely to see the Bronco sit out a game due to suspension) that attracted the most attention.
While Kiwi captain Simon Mannering distanced the team from the gesture post-match, saying "that's not us", it's that same fiery aggression and passion that makes Taupau such an asset to the Wests Tigers.
Back-rower Dene Halatau – a veteran of 15 Tests for New Zealand – was as pleased with Tauapu's form as he was with New Zealand's third straight win over Australia.
"Marty had an immediate impact and he did that last year in the Four Nations as well, that was his role, he came on and really got them moving forward and was really aggressive and played a good style of footy," Halatau told NRL.com.
"He does it for us too, that's the way he's been for us. We know he's very valuable for us on the field because he puts a dent in the defensive line. He's very busy."
Halfback Luke Brooks also welcomed the platform Taupau's aggression has provided him and fellow young playmakers Mitch Moses and James Tedesco.
"Taupau was outstanding when he came on for the Kiwis, he got them rolling, then off the back of that they got a few tries," Brooks said.
"You need to have a bit of aggression in your forward pack. He's just playing awesome this year. It's good to play off the back of him, he gets some quick play the balls and in defence he's good as well."
Taupau is far from the only forward making an impact for the Tigers in 2015; Kangaroos prop Aaron Woods is easily the top metre-getter among props in the NRL, averaging 215 metres per game – 50 more than the next best prop, Cronulla's Andrew Fifita.
Sauaso Sue is having a breakout year, while Curtis Sironen and Kyle Lovett have made the edge back-rower roles their own and the understated Ava Seumanufagai also earned praise.
"These young guys coming through, guys like, Kyle Lovett, it's been great to see a guy like him [cement a first grade spot]," Halatau said.
"Every year since I came back he's worked hard in the pre-season, he's a great guy to be around, he's earned the spot in the team and he's doing great for us.
"Curtis Sironen, he's a talent, and he was rewarded with a City jumper on the weekend and he's doing really well for us.
"There's a couple of guys that don't get the mention, like Ava Seumanufagai, he's been really good, Jessie Sue's done a really good job, this is maybe his breakout year, he does a good job in every game and does all the little things really well and he's pretty hard to handle."