England's current dominance at the top of the world game is unquestionable, but a year ago the facade almost cracked.

They ultimately held on to take the title, but it prompted change.

In August of that year, former Leicester and England lock Louis Deacon stepped in as forwards coach.

Since then, the Red Roses have claimed record victories against world champions New Zealand, extended their impressive winning run to 21 in a row - and are now bulldozing a path towards a fourth successive Women's Six Nations title.

Recently, few teams have challenged England up front the way France did 12 months ago.

England's scrum is strong and their line-out has become a potent weapon that has contributed to many of the 31 tries scored in their last three games.

However, despite having such a big impact already, Deacon says "we've only scratched the surface".

"I think there's still more to come, that's the exciting thing," the 41-year-old tells BBC Radio 5 Live's Rugby Union Weekly.

France will be 'ultimate test'

The scrum is sturdier than it once was, but as with all top sides England will not stop until they have achieved perfection.

So far this Six Nations they have won three opposition scrums, lost two of their own, conceded three scrum penalties and won seven.

The line-out statistics are much more impressive: they have won 45 and stolen seven from their opponents, with Wales the only side able to steal one back.

Deacon says "the scrum has improved massively", but believes much depends on how England fare on their trip to France at the end of the month - which many expect to be the Women's Six Nations decider.

"The ultimate test will be France," he adds. "Looking at their game, the scrum is a key area for them.

"We've got some tactics we think will help us with that against the power they've got in that scrum."

'My focus is on winning the World Cup'

Before France, England take on Ireland at Leicester's Mattioli Woods Welford Road ground as they seek to continue their unbeaten run in this year's Six Nations.

For Deacon it is a homecoming under circumstances he would never have envisaged.

He had been part of Coventry's coaching team in the men's Championship when he was called into the England set-up.

Having earned 29 England caps and made 274 appearances for Leicester between 2000 and 2015, coaching with the Tigers as his younger brother Brett does might have been a more expected move.

Although playing for Leicester was a boyhood dream and Deacon says he would "love to go back there and coach", he only has one thing on his mind at the moment.

"The focus is to go and win the World Cup," he says of the tournament which begins in New Zealand on 8 October.

"That is the biggest goal for me at the moment and I'll do everything I can from now until then to give ourselves the best chance."

A record crowd is expected in Leicester, likely to surpass the mark of 14,689 set in Gloucester earlier in April, and they will no doubt offer Deacon a warm reception.

"It's a great stadium to play in," he says. "Having a large crowd in Welford Road will be amazing.

"I've not been back there in a coaching capacity so that will be really nice."