NRL coaches successfully argued against an obstruction rule overhaul 18 months ago, admitting they would flood the game with block plays if the "inside shoulder" interpretation was relaxed.
Head of football Graham Annesley revealed the machinations of a coaches conference in November 2018, when he pitched reshaping the obstruction rule to the likes of Trent Robinson, Des Hasler and Brad Arthur.
Annesley himself was convinced the rule that sweep runners "must receive the ball beyond the inside shoulder of the block runner" had to go.
But when he put it to the coaches in attendance, and admittedly as many as half of the NRL's clipboard carriers weren't, they were resolute.
Relaxing the black and white rule would only be to rugby league's detriment, with NFL-style blockers and decoys multiplying in a bid to crack increasingly watertight defences.
Everything you need to know about the obstruction rule
"When I discussed it with the coaches they made it very clear to me that they were very comfortable with the interpretation," Annesley said on Monday after several round-five decisions sparked debate.
"And the reason for that, and they were very outspoken about this, if you take that rule away they will load up with many more lead runners and decoy runners.
"I must admit when I came back into the [head of football] role, I was pretty convinced that we needed to get rid of that rule.
"I thought it didn't necessarily have an impact on whether people were actually physically obstructed or not.
"In some cases tries were being disallowed based purely on the inside shoulder rule, when it was difficult to see if anyone had been obstructed.
Graham Annesley weekly football briefing - Round 5
"But I was convinced at the time by the head coaches that it was beneficial to retain the interpretation of the rule.
"Because the last thing that anyone wants to see is our game opened up to more blockers and decoy runners that will lead to not only less tries or more tries being overturned, and more controversy."
Seven obstruction rulings were referred to the NRL bunker over the weekend, an above-ordinary figure believed to have been contributed to by fatigue and the new six-again ruck interpretations.
Former premiership-winning coach Phil Gould raged against the inside shoulder rule while commentating for Channel Nine in Sunday's Dragons-Sharks clash.
Gould argued a denied try to Cronulla's Shaun Johnson – because Will Kennedy took a Blayke Brailey pass on the inside shoulder of his decoy runner, Jack Williams – only rewarded Ben Hunt's poor defensive read.
NRL Bunker manager Jared Maxwell said the inside shoulder rule was introduced to reduce the discretion around such decisions and create greater consistency on obstruction rulings.
Bunker denies try to Johnson
Elsewhere Annesley confirmed Knights prop David Klemmer had been incorrectly penalised for contact on decoy runner Dale Finucane, a call that killed off Newcastle's comeback against Melbourne with a late penalty goal.
Annesley said Klemmer's was an "accidental collision" with Finucane and did not warrant a penalty.
Following the referees' round-five review the NRL also found a try to Titans forward Bryce Cartwright had been incorrectly denied by the Bunker in their loss to South Sydney.