One of the more cogent pieces of surfing advice I've read is this: When riding steep waves, always treat the surface as if it was flat. Try and keep your board on the same plane as the pitching wave. I've held onto those words, if not always put them to use, because of the person who uttered them - Kelly Slater, then a mere five time world champion.

That advice is worth recalling now as Slater pushes his modern Banana board, shaped specifically for steep, barrelling waves. The Banana theory, at least how Slater is plugging it, is that the curves of the board match those of the waves it's intended for. They lay 'flat' against the surface.

The difference with current thinking around the Banana, as opposed to when it first came out in 1992, is that they're not being sold as all round boards. The marketing is tilted as a next level design for next level waves. Which makes it a wee bit baffling why Slater chose to ride his at wobbly Snapper, but then who wouldn't be excited with a sexy new Ferrari in the garage? The trick, of course, is spotting when the race track turns into a goat track and adjusting accordingly.

Slater slices a Banana at the 2015 Pipe Masters

In 1992, Taylor Steele's Momentum captured the surfing zeitgeist. At the time Kelly Slater and Al Merrick brought their widths down under 18 inches, and Shane Herring and Greg Webber were pushing their rocker and concave experiments.

There's a certain irony that the favoured board of the 'Momentum' generation was sluggish for the hoi polloi. When surfers rejected the banana theory en masse they didn't have to wait long till a countervailing design became available. Andrew Kidman, Derek Hynd, and Tom Curren had much to contribute to the canon yet their cause was aided by a surfing public jaded by curve. By 1995 Fish/Fireball/Stub Vector had entered the lexicon and low-rockered boards kept the momentum even when the wave didn't allow it.

Yet while the Merrick/Slater experiment of thin and narrow found its zenith and width gently returned to surfboards, the Webber/Herring experiment faced universal condemnation. People said the idea was extreme, however the reaction was equally as bad. Herring's demons rode the design into the dust where it lay for twenty years.

Old 'nana, new 'nana, with a wafer thin side dish

Slater surprised everyone when he resurrected the design in late 2014. He's never been averse to left-field ideas but this one was more intriguing than most. He teamed up with past-rival Webber, the two building on the old theory, and then recently began mass producing them under the Slater Design label.

First impressions of the modern Banana are that it's not as rockered out as expected. Everyone I handed it to had the same response. Kelly and Greg have notably toned it down, it has around 1/4 inch less nose lift than those early 90s Insights. What it does have, however, is a smooth continuous rocker from nose to tail, plus a simple deep concave that begins near the nose and continues past the feet, through the fins, and bleeds off the tail. The mix of these gentle, ceaseless curves is sublime; while handling the board the far rail gently rises and falls against the near rail that traces both rocker and planshape. The feeling, especially when compared against the original Banana boards, is of agreement between all the features.

The only detail that stands out is the hip, however it's inclusion lets the rails between the feet stay straighter, and also reduces the width in the tail, further emphasising that this is a board for good waves.

"The feeling  is of agreement between all the features."

It's got a five fin set up and first sessions were ridden as a thruster which proved troublesome. As expected the board was hyper-reactive, telepathic even, you only have to think about a turn and the arc begins. But by switching to a quad set up – which is how Greg Webber intended it to be ridden – a nano second of lag time was provided to weight the board. Four fins also increased the variables that could be taken into a turn and allowed the board to run a bit when exiting a turn. Call it a safety net for non-pro surfers.

Though it's straighter than 90s 'nanas the rocker is still apparent. If you're riding it in anything less than the waves it's intended for – and plenty of times I did – then you've gotta choose your wave, choose your line, and choose your turn. Keep it close to the pocket or else.

The crux of Webber's theory is matching the curve of the board to that of the wave, this extends beyond Slater's opening quote – ie the board lying flat on the wave - to how the rocker is cradled within the wave. When you make the right choice and sink the rail in a steep section the rocker seeks a path of least resistance through the the water. When it happens the feeling is electric. Turns feel effortless. Kind of slippery...and the Banana name takes on new meaning.

In these 'slippery' moments the board tracks through the wave so well it simply doesn't displace water. Think of a diver entering the water off the 10 metre platform - little splash and little spray. The sensation is wonderful but how would it be judged if it were in competition? Spray is the gauge of effort, right?

There's plenty of cud to chew on here, especially considering the theory at hand: is it better that a surfboard cleaves the water cleanly, or does it need to push against its heft? Should it follow an easy path, or should it have some resistance?

These aren't questions a non-pro need consider – me, I'll simply enjoy the slippery sensation - but the cold fact is the popularity of the Banana rests solely on how Kelly Slater performs on it this year. He's been filmed tearing on them outside of competition at Duranbah and at Cloudbreak, even in his wave pool, so they clearly perform under his feet, yet it'll be how he performs in competition that saves the Banana from condemnation take two.