The electric lightbulb. Aeroplanes. Post-it notes.

History is littered with inventions that experts dismissed as pointless, only for them to become so important that it would be impossible to imagine life without them.

The same could be said – in the snooker world, at least – of SightRight, a patented sighting aid that provides players with a straight line of aim.

Given that snooker is a game of accuracy, precision and technique, it’s easy to assume that such a thing is a pre-requisite. Not true.

According to SightRight’s creator, Stephen Feeney, 99 per cent of all players sight their shots "from the wrong point of observation", something physicists refer to as a 'parallax error'.

In snooker terms, it means they line up a shot with their body rather than their eyes.

"They think that they're seeing a perfectly straight line of aim," says Feeney, "when in actual fact they're looking across it."

That, clearly, doesn’t stop players from becoming world-class. But it doesn’t make it any easier, either.

"I liken it to a marksman," says Feeney.

"You wouldn't ever have someone shooting a rifle if they're left-handed on their left ear, or if they're right-handed on their right ear, but I can show you many top players who line up a shot that way."

Feeney blames "old-fashioned methodology" for the prevalence of such errors, which he says are "either inherent in the individual, in the way they've learned to play, or actually coached in".

In Feeney’s experience, it was a combination of the two.

"I went through a terrible time as a player," he says. "I picked up a well-known coaching book – I’m not going to name it – and I destroyed my game through following these methods."

Those methods – which include age-old teachings such as "right leg on line" for a right-handed player, and "left leg on line" for a left-handed player – troubled Feeney, who wanted to know whether he was "sighting a straight line of aim correctly".

"I went to see some of the best snooker coaches in the land at that time," he says, "and those individuals did not resolve my problem.

"They couldn't tell me. No coach could tell me."

So Feeney endeavoured to find out for himself.

"I kept playing around with different things," he says, "and I came upon this method of how to check whether I was seeing straight."

What Feeney had created was technology which enables him to see through the eyes of any player and give them a sighting line that is specific to their vision.

His invention, however, was not warmly received in the beginning.

"Mark Williams would call it 'SightWrong' in the early days," says Feeney. "It wasn't fully understood."

It’s easy to see why successful pros didn’t appreciate being told that their methods – which have been used throughout the snooker’s entire existence – are, in fact, flawed.

Consequently, it has been players who are either struggling or looking to propel their careers to the next level that Feeney has tended to work with.

Stuart Bingham used SightRight when he won the 2015 World Championship, while this year has seen two world champions, Mark Williams and Shaun Murphy, team up with Feeney.

The decision of Williams in particular was a surprise, given his previous public criticism, but the impact it has had on his form has been emphatic.

Having not won a tournament in six years, the 42-year-old Welshman has since triumphed not once, but twice, most recently at the Northern Ireland Open.

It was Williams’ U-turn, coupled with his frustration at being unable to fix long-standing faults in his game, that prompted Murphy to call Feeney.

The Englishman’s form has flourished ever since.

Murphy finished as runner-up in consecutive tournaments in China and Germany after the pair’s first session together, before beating Ronnie O’Sullivan in the Champions of Champions last month.

"There's nothing more rewarding than when you see them lift that title," says Feeney. "Especially when they haven’t won a title for a long time."

Feeney describes himself as a "performance-based coach", meaning he only gets paid if the player achieves pre-determined targets.

And while he doesn’t guarantee that everyone who he coaches will become world No. 1 – "people will have different achievement levels" – he does guarantee to show them "the truth".

"The timing of your cue action, the pause, the grip, everything else that goes in play, is second to this," says Feeney.

"Once I learn to see through their eyes, I can help them do exactly what they need to do every time."

Shaun Murphy: 'The difference was significant and immediate – I can’t thank Steve enough'

When Steve explained the technicalities of SightRight, I understood it straight away.

My first session was just before I went to Guangzhou for the China Championship, where I reached the final. And then I went straight to the Paul Hunter Classic, where I was runner-up again.

People out there will say: 'Well, you've been runner-up many times and you've won lots of tournaments before.'

But I know that the difference was significant and immediate, and I can't thank Steve enough.

We're all taught out of the Joe Davis manual to stand right foot on line – it makes absolutely no sense whatsoever, because that's nowhere near where your eyes are.

What Steve’s done is to demonstrate absolutely that when making decisions, I'm actually stood in the wrong place for my own vision requirements.

I'm not potting every ball I look at by any stretch. But there are shots I've consistently struggled with since I was nine years of age that I now don't struggle with.

What SightRight has given me is – and this is going to sound strange – but when I do miss, I get the miss that I'm expecting.

A lot of people think I'm being paid to promote SightRight. It's not true – there’s only one way the payment goes, and it's from me to Steve for his time and his advice.

I think, like most people, when Steve first came on the scene, myself and others were very sceptical.

There were jokes on tour, there was a bit of banter – 'SightWrong' and worse - and then I saw Mark Williams tweet that he'd started working with him.

No-one on tour had given Steve Feeney as rough a time as Mark, and I thought: 'Well, if he's giving it a go, and speaking positively of it, there must be something in it.'

That coincided with just becoming unbelievably frustrated with not being able to fix these faults. I'm a very good long potter, but why aren't I able to play this shot over distance?

I was practising with Matt Selt and I said to him: 'Do you know what? I might just give Steve Feeney a call.'

I invited him to the house for lunch. He walked me through it and gave me his sales pitch.

When he got to the moment of reveal, like a magician revealing his trick, I was all ready to say: 'Steve, thanks for coming, thanks for your time, but it's a no from me.'

He said: 'Do you think you're stood in the right place?' I said yes.

And he's got his gizmo, which tells you whether you are or not for your own vision, and he made the reveal, which demonstrated I was stood in the wrong place.

It just blew my mind.

SightRight’s changed long, thin safety shots for me.

I've played so many shots where I'm trying desperately to catch the thin coat of paint of the red and I end up hitting it half ball. It's such a bad shot, I'm so far out.

Now, when I play for that extreme edge, I might miss the ball altogether, but that's much better than hitting it full in the face and leaving the white down at the wrong end of the table.

I'm not potting everything I look at, but I'm getting much closer.

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