Seven years under the microscope have left Australia's scrum performance as unpredictable and as vulnerable to criticism as ever. Will this weekend's England Test be a repeat of the pack's Twickenham triumph last year or another round of the pain dished out in the British and Irish Lions decider?

No less important - what perceptions will the referee bring to his adjudication of the contest?

New laws, which effectively neutralise the ''hit'' at the scrum engagement, and turn the set-piece into a wrestling contest, have muddied the waters further. But captain James Horwill said the team's five-Test tour of Britain, Ireland and Italy presents the Australian pack with an unmissable opportunity to claw back some respect.

''The northern hemisphere is always a big-forward-oriented game, and if you can set the platform for our backs then that goes a long way to winning a game,'' Horwill said.

''The weather conditions may come into play up there at this time of year, so it could completely change the way the game is played if it is raining and windy. We'll need to be able to adapt but it is a big opportunity for us, a chance to stake a good claim for your reputation as a good forward pack.''

England are at the start of their international season, and have not played under the new scrum laws.

Horwill said the Wallabies were better for their seven-Test experiment under the new regime but he stopped short of saying England were at a disadvantage.

''It depends on what the referees are looking for,'' he said. ''Early on when the [changes] first came in [the International Rugby Board] weren't exactly sure what they were looking for initially.

''It changed for the first three or four weeks; there were different things they thought would work. I think they've got to where they want to be now and what they want the referees to look for, so we'll just work within that mandate.''

Horwill has not been on a full spring tour since 2009. He made the shortened, one-Test trip after the 2011 World Cup but sat out last year's tour with a hamstring injury. He watched from home as replacement captain Nathan Sharpe led the side to a momentous 20-14 victory at Twickenham.

''This trip is going to be really good for this group,'' Horwill said. ''Five weeks away, we can eliminate distractions on the outside and just focus on trying to mould the group together and work hard on and off the field.''

It will also be something different. After a Super Rugby season and the Rugby Championship, the Wallabies have had their fill of New Zealand and South African opponents.

''[England] play a bit different to New Zealand and South Africa,'' Horwill said. ''They're not as hard on at the breakdown but they're very set-piece focused. They look to get ascendancy at the scrum and lineout. They work very hard on that, like most northern hemisphere teams do.''

Horwill carries a dark secret in the form of a British passport. Although he was born in Australia, his mother is English and grew up a few blocks from Twickenham. She will be at the match with a close friend on Saturday, but in a gold jersey, Horwill happily confirmed.

''I'm a bit biased, I have a foot in both camps … But it's big brother, Australia like beating big brother,'' he said.