WE all know well enough that the goalposts in rugby union can shift at any moment.

At present, a one-up, one-down system is in place between the Zurich Premiership and National One until 2009 -- but will those rules last the distance?

The rumour mill is in overdrive at present with speculation of deal and counter-deal being bandied about for the National One clubs.

The belief is that the majority want to keep the status quo but, with a number of parties pushing for yet another shake-up because of possible financial sweeteners, things could yet change.

Certainly, Premier Rugby Ltd's chief executive Howard Thomas is in favour of another review.

"Promotion and relegation can only work where there is a natural seam between two leagues," he said. "Most professional sports in most countries do not have it.

"The financial drop between the Premiership and National One is of such a magnitude that there is no way a business can survive relegation. The only way you can readjust to operate in the league below is to have mass redundancy.

"Financially, it is more than a 10-fold drop. In football terms, it is like going down from the Premiership to the Conference. Football has a cushion -- the Coca-Cola Championship is financially viable."

Worcester have, so far, kept their heads above the relegation waters since their promotion from National One. However, the Warriors have their millionaire-backer in Cecil Duckworth to keep them afloat.

Many clubs do not and relegation for the top sides would be a financial disaster.

"No Zurich Premiership club can adjust to be financially viable in National One," added Thomas.

"The revenue streams are not there. The league has no commercial sponsor and no television income. Relegated clubs have to have a wholesale change of players. The gulf in playing standard is also huge. Worcester have been able to adapt, and their achievements this season are outstanding, but that is not the norm.

"I would advocate that we should always have the best 12 clubs in the Premiership.

"Having a promotion-relegation play-off is the best way of testing that. You could give the National One club home advantage. You definitely need some sort of review.

"If you operate a 12-club franchise, and one team for example finished bottom two years out of three, then you could have a play-off. What you don't want is a lame duck."

With First Division Rugby (FDR) still in favour of the continuation of promotion and relegation, however, rugby's most famous squabble shows no signs of abating.

Former Sixways chief executive Geoff Cooke is a fervent advocate of promotion and relegation.

As executive director of FDR -- the body representing National One clubs -- it is Cooke's job to lobby for promotion.

"I believe in promotion and relegation," said Cooke, who is also director of rugby for Bradford and Bingley.

"It is simple. For a league system to be successful, it has to have promotion and relegation.

"There is not one successful league system that doesn't have it, apart from those made up of franchises.

"You have got to give clubs an incentive to progress. For National One clubs, the dream is to play in the Premiership. It doesn't matter how hard it is, that's the dream. That's what promotes support and investment.

"The converse is that if you didn't have promotion and relegation, what would Harlequins and the other clubs in the bottom six of the Premiership be doing now? They would have nothing to play for.

"Who would go and watch a game when the result doesn't matter?"