As Trenton Oldfield swam out to put himself in front of the armada of craft following the Oxford and Cambridge Boat Race it must have seemed to him like the full weight of the British upper class was bearing down on him. Two blue boats full of privately educated toffs; launches full of investment bankers, highly paid lawyers or consultant surgeons. Outside of throwing himself under Prince Harry's polo pony, it seemed, he couldn't have chosen to disrupt a more elitist sporting event.

When you glimpse the perfectly manicured lawns of Henley Royal Regatta, or wander through the stunning surrounds of Eton College's private 2000m rowing lake, it's hard not to think of rowing as an elitist, or exclusive sport. Unless you've got rich parents, a posh name – sorry, Trenton – or aspirations above your station, find another sport.

While that's a view that might comfortably conform to the cultural stereotypes of another century, it bears little relationship to how I've seen either the Boat Race, or British rowing change over the past 30 years. The sport's international success has helped drive an elitist agenda – not one based on social class but instead performance.

The standard bearer of that drive was my 1984 Olympic crew-mate, Steve Redgrave: a comprehensive schoolboy with just one GCSE to his name, who beat all-comers. His success in five Olympics between 1984 and 2000 helped fund the sport's drive to find the biggest and the best – from whatever walk of life. A mixture of both state and commercially funded programmes opened up a pathway of diversity in rowing.

The results of those performance-driven programmes are clear. Almost half of the likely British team for the 2012 Olympics were educated at a state school. Many of them learned to row as a result of programmes such as Sporting Giants. In particular, the selection in the British eight of Moe Sbihi, who attended a Surrey comprehensive, provides just one example of how far the sport has come.

Outside of the new intake, British rowing owes as much to its proletarian as its socially elite roots. As Christopher Dodd's new book Pieces of Eight has shown, British rowing's international renaissance was significantly energised in the 1970s by working-class men from the Thames Tradesmen's Rowing Club. One of them was Jim Clark, who taught this state schoolboy how to row. Even in 2012, the heritage of the professional watermen is still very much alive in the British team, through the presence of Beijing Olympic champion and "East End lad" Mark Hunter.

But unless you're a rower, those nuances are likely to have passed you by. Rowing is a sport that – outside of the Olympic Games – usually flies well under the radar of most sports editors. So it's perhaps unsurprising that the public's perception of the sport is rooted in outdated cultural stereotypes.

Even the Boat Race has changed out of all recognition. To some of my fellow national squad rowers in early 1980s, the crews from Oxford and Cambridge were often regarded as a bit of a joke. With the odd exception, the blue boats seemed to be stuck in a time-warp, made up of an exclusive club of British private schoolboys, with posh accents whose eights were often not that fast.

Fast-forward to 2012 and it is a different world. A ruthless performance-based agenda has changed the boat race brand out of all recognition. The two multinational eights are right up there with the best in the world. Unless they are incredibly talented, most British private schoolboy rowers who gain places at Oxford or Cambridge would struggle to find a seat in either blue boat.

The two crews that Oldfield recklessly stopped in the middle of an enthralling contest were actually far more representative of the level of excellence that we see in elite-level international sportsmen and women, than of any social elitism of a bygone era.

Those eighteen blues had won their places on the start-line through their willingness to submit to an extraordinarily tough training programme. They, in common with the vast majority of rowers in the world today did that, not for financial gain – there is no money to be had in rowing – but for challenge, team-spirit and the deep satisfaction of personal achievement.

The rowing community at least, will remember Oldfield's stunt as a misguided assault on the values they hold dear.

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