Latest model: the Gilbert Virtuo, complete with new bladder, valve shape and valve weight, will be used at this year's World Cup.
Can they kick it? Scotland's Chris Paterson landed all 17 of his goal kicks at France 2007 with the Synergie ball.
I'm sitting in an office in the East Sussex village of Robertsbridge, talking balls with Gilbert Rugby's chief research and development engineer. Or inventor for short. For the fifth time running, it will be a Gilbert ball that the globe's best players will be passing and kicking at the Rugby World Cup, and perhaps cursing if mistakes creep into their game.
In 2003 Fiji blamed the "slippery" silicon covering for their error-strewn display against USA, while four years later there were mumblings about the ball from New Zealand after Dan Carter missed five out of nine kicks against Scotland.
And of course there was Jonnygate. French tweak Wilko's balls screamed The DailyStar, alleging that French officials may have deliberately over-inflated the balls to put Wilkinson off his goalkicking. The fly-half's kicking success ratio had dropped by nearly 20% and a casual remark to journalists that he was struggling to cope with the ball prompted a wave of articles.
"The issue in 2007 was that match officials were over-inflating the balls, even though they were all given instructions," says Savage, 32. "Half a psi (pounds per square inch of pressure) makes quite a difference. Over-inflated balls are harder to kick, harder to get energy into."
In Wilkinson's case he had also missed a lot of rugby, though no one can plead lack of opportunity to practise. International teams have been using the 2011 World Cup ball - called the Virtuo - for the past year and everyone receives a batch for their training camps, and then 30 more at the World Cup. On match days teams get four for the warm-up.
Not for nothing are Gilbert the name everyone associates with rugby balls, the ball of choice for the World Cup, Aviva Premiership, Magners League and Super Rugby. Only five of the 20 teams at RWC 2011 don't use Gilbert balls for home Tests, with New Zealand (Adidas), Wales (Webb Ellis) and Italy (Mitre) the main exceptions.
So when someone criticises his ball, a bit of Savage takes it personally and the sports engineering graduate from De Montfort University in Leicester (final-year dissertation: flow visualisation of rugby balls) sets his mind on making the perfect ball slightly more perfect.
Thus when Fiji said the ball was slippy, Savage thought pimples. "Every pimple is round," he reasoned, "but what if we try a new shape?" So he tried eight different shapes and found that a star shape worked best.
And having personally weighed and measured each of the 288 match balls, by hand at France a process he repeated four times at various stages for each ball, he has now invented a copolymer construction that doesn't allow air out of it but has the same resilience, so you can pre-inflate balls to the right pressure without fear of the pressure falling throughout a game.
"For 2011 I've left the pimple height the same but have changed the bladder and valve. The valve is a different shape so has better rotational consistency. Distributing the weight of the valve in a different way makes the ball more stable when rotating so, for example, for spin passes and torpedo kicks the ball will be more stable." Gilbert's valve - in the seam - is one of their most significant patents.
It's all a far cry from 1832, when William Gilbert, a shoemaker to Rugby The School, made the first balls specifically for the was by sport - cowhide leather encasing an inflated a pig's bladder. It was the bladder that gave a rugby ball its distinctive shape, although the plum shape familiar to us today arrived in the 1870s, shortly after Richard Lindon, a former pupil of Rugby School, invented an inflatable rubber bladder... after his wife died from a disease caught while blowing up a pig's bladder. In 1892 ball dimensions were standardised, with only four panels permitted, and 40 years later the ball was reduced by an inch and the weight increased to make it easier to handle.
The real revolution, of course, came in the 1980s when leather gave way to synthetic rubber. "That was massive jump because rubber can be moulded and is waterproof," explains Savage. "Leather absorbs water and ball can be 20-30% heavier by the end of a game in wet weather. It's also slippier because the ball has no pimples. When you see old pictures of players running with the ball in both hands, it's not just because it's good technique - you needed both hands to control it."
But how on earth did post-war All Black Bob Scott manage to hoof a heavy leather ball vast distances in bare feet?
"Leather is softer than rubber so there's not the same stinging sensation. And bare feet provide better strike characteristics because there's no footwear to take away energy from the impact." Obvious really.
No two cowhides are identical so the exact shape of a ball used to be down to the craftsman. Now, with modern manufacturing, all balls should be the same, though the process is more complex as you're laminating a lot of layers together. But is all this tweaking and tinkering really necessary? "Each time we launch a ball it's an improvement on what has gone before," answers Savage, "and you have to look to the past to move forwards. You can still buy the Barbarian ball, used in the 1995 World Cup. But each World Cup ball improves on certain things because the bladder technology, the pimple technology, moves on. For example, we looked at using Kevlar inside the ball but it's very pricey and it's too strong, so it's not possible to impart the required energy in the ball."
Mitre (1987) and Adidas (1991) provided the early World Cup balls, with France fly-half Didier Camberabero rather rudely calling the latter's Webb Ellis ball a "mixture between soap and a balloon - it slips through your fingers when you try to pass it, and flies like a loose rocket when you try to kick it".
Gilbert have supplied the ball ever since. Their Barbarian was used at South Africa 1995, and for 1999 they created a new rubber compound, so the Revolution ball was more responsive and easier to grip. Less ink made it less slippy.
In 2003 a more aggressive pimple pattern - higher but fewer of them and further apart - made the Xact ball still more 'grippy' without any loss of aerodynamics. But feedback (mainly those pesky Fijians) suggested that in dewy conditions the ball was slippy. It needed a bedding-in period and some of those used were newer than players were used to.
So for France 2007, Gilbert developed a new grip for their Synergie ball. It was the first World Cup ball without the company's trademark ellipses and had more of a tournament feel, with the trims taking inspiration from the RWC logo.
This year's 460g Virtuo, which is decorated by Maori imagery of the hammerhead shark and fern shoot, was recently launched in South Africa and New Zealand. Yet Paul Grayson, the former England fly-half who Clive Woodward once rated as the world's most accurate out-of-hand kicker, has been using it since early 2009 in his capacity as Gilbert's ball tester.
Total Rugby: Gilbert Ball Making by IRB
"It's the best ball Gilbert have ever made and reflects the work that has gone into it," says the Northampton assistant coach, who kicks into a wind when testing because balls always behave better with the wind behind you. "All players like to feel comfortable with a ball and the Virtuo has great feel to it. It behaves as you want it to and the accuracy is consistent no matter how you kick it - end-over-end, spiral, drop-kick, anything.
"The bladder technology gives the ball greater reliability. You want to know if you have ten match balls that they'll all be the same and this does that. The valve design makes it incredibly stable in flight, whether it's a spiral kick or spinning back as in a goalkick. When you hit it correctly you know it's on your side, it's going to fight for you."
Stats are a closely-guarded secret but I can reveal that the Xact ball had a 7396 goalkicking success rate, compared to 7496 for the Synergie in 2007. Well, you know what they say about small margins. Kick stats aren't down to the ball alone, of course, but Grayson believes even a layman could tell the difference between the Virtuo and the Xact that Wilkinson popped over in the last minute in Sydney.
"A big part of it is cutting out the variables," he adds. "You don't want to kick a ball and think, 'That didn't feel right'. These balls aren't made to last 25 games, these are Formula One balls (with an E80 price tag) and they have to perform under the most extreme pressure. The equipment has got to stand up to that level of examination."
They say racquet technology made tennis serves too powerful, that equipment advances made golf courses too small. Tennis introduced high-altitude balls for different atmospheric pressures, something FIFA might wish they had tried at last year's Football World Cup in South Africa, when players repeatedly over-hit the highly pressurised, hard-to-master Adidas ball.
Rugby won't make that mistake. "Measurements are based on consistency and accuracy, not distance," Savage says. "If the IRB wanted us to make a ball that could travel further we could do it, but we're not here to change the game or its laws.
"If you asked ten different players they would all want something different from a ball. Our objective is simply producing a ball that behaves consistently so that players can perform with confidence."
Over to you Jonny, Dan and you ball-chucking Fijians.
Alan Pearey - RugbtWorld.com
Date: July 2011