Dozens of the world's top curlers, including Olympic gold medallists Brad Gushue, Brad Jacobs and Jennifer Jones, say they won't use new broom technology that threatens to alter the sport dramatically by slowing down and changing the direction of a rock in motion.

A statement posted on Team Canada's website has been signed by at least 34 elite curling teams, saying they will not sweep with brooms that have "directional fabric" at World Curling Tour, Curling Champions Tour and Grand Slam of Curling competitions.

The move comes as the curlers wait for the sport's governing bodies to catch up and introduce new rules on broom technology.

"We want the skill of curling to determine who wins and we want the teams who've put in the hardest work to win. We don't want the teams with the best technology and whoever sponsors who to win," Team Canada lead Nolan Thiessen, who wrote the statement, told CBC News on Friday.

When a new gadget fundamentally alters a sport, the powers that be often step in and declare it illegal in competition.

Curling's top teams aren't waiting for the World Curling Federation or Curling Canada and are policing themselves. They hope other teams follow suit.

The statement was signed by 22 elite teams on Wednesday, including Gushue, Jacobs and Jones as well as former world champion Glenn Howard and international curlers such as Jaap van Dorp of the Netherlands and Niklas Edin of Sweden. Another 12 teams were added to the list of signatories on Thursday.

Changing the game

In the sport, a curler throwing the rock aims for the skip's broom with the knowledge the stone will curl as it approaches the house.

Powerful sweepers can "hold" the stone and delay its curl or "drag" it extra distance into the house, but throwing accuracy and the skip's line calling are still paramount in the game.

Hardline Curling president Archie Manavian says his company had not received any complaints about its product, the icePad, until the curlers' statement came out this week. (CBC) New brushes hitting the market have recently changed all that.

"It's a type of fabric that allows you to virtually steer the rock," Howard told The Canadian Press. "I use the phrase 'joystick'. I can now joystick right, left, forward, back."

Coarse material on the broomheads creates a sandpaper effect on the ice. Jacobs describes it as "flattening" while others have described it as "scoring" or "scratching" the ice.

The bottom line is sweepers use the brush's impact on the ice to manipulate the rock in ways they never could before. As in any sport, if others are doing it and winning, you will do it too.

"It's like having a rock with a steering wheel on it and you can pretty much get it to go where you want to or influence it substantially," said Curling Canada's high-performance director, Gerry Peckham.

'Players love it,' company says

New brushes include the icePad from Montreal-based Hardline Curling, which got its break on CBC's Dragons' Den in 2014.

"It is the most effective brush on the planet right now," Hardline president Archie Manavian told CBC News.

"The players love it. We've never had a complaint about it up until today. Up until this week, let's say."

The icePad uses new cloth technology that helps the rock glide. Some call that technology "directional fabric," but Manavian said his company is being unfairly characterized by its competitors.

"We've basically just taken over the market and, you know, there's one competitor in particular who's not too happy about it," he said.

Brushes 'tarnishing' the sport, says competitor

The debate over directional fabric came to a head this past week at the StuSells Toronto Tankard when another company, BalancePlus, showed off prototype brushes that exaggerate the icePad's technology to demonstrate how drastically it can affect the rock.

Gushue told The Canadian Press that teams using the latest version of the broomhead caused the ice to deteriorate in Toronto and ruined subsequent shots.

Scott Taylor, president of Toronto-based BalancePlus, says directional fabric on brush heads has no place in curling.

"One company's product seemed to be leading the way in the development of 'directional' heads. Other companies and individuals have also gone in that direction. Whether it was done on purpose or simply by mistake, hopefully all of them will do the right thing and stop using directional fabric," he said in a statement posted on the company's website late Friday.

"This 'directional' equipment change has crossed the line," he added. "It is tarnishing the great reputation of our sport."

BalancePlus says it never intends to sell or distribute the prototypes it demonstrated at the competition.

Thiessen, the curler behind the statement, is sponsored by BalancePlus. However, he said that's not why he's speaking out on the issue.

"We're just trying to be leaders as the elite teams and just asking for our governing bodies to determine is this what we really want in the true integrity of the game?" he said.

Curlers want clarity

Among those who use the icePad is Saskatoon's Steve Laycock, who was competing at the Canad Inns Prairie Classic competition in Portage la Prairie, Man., on Friday.

"We saw how effective they were when other teams were using them. Our experience hasn't been that they really break down the ice," he said.

"We definitely do think they are kind of at the peak of what effectiveness would be."

However, Laycock has also signed the curlers' statement in a bid to call on curling authorities to give some clarity on what brushes are acceptable.

"Some of the brooms that have been made now — you'd be able to, having never curled in your life, to walk out there and have a rock back up four feet," he said. "That's probably more than what we want right now in our sport."

Laycock said his team will abide by whatever official guidelines are set out.

There have been several broom technology advances since curlers put down straw and cloth brooms and picked up brushes 40 years ago, but none this dramatic, Peckham said.

He said Curling Canada, in conjunction with the WCF, will address the broom issue even if it means calling a moratorium on directional fabric until further study.

"We have to take a look at performance thresholds, like how much is too much, and how do we determine that?" he said.