Promotion from the National Leagues to the near-heavenly plains of the Premiership is generally assumed to be an experience similar to stepping off a tube train in London Underground - a mass of humanity shoving you backwards as you try to maximise a five second window of opportunity with constant warnings to 'Mind the gap'.
The difference between the two levels, we are 'reliably' assured, is so hazardous it's really best not tried at all. Just look at Rotherham.
Not only did they they fail to span the divide, they fell unceremoniously between carriage and platform with 22 defeats from 22 games and just three league points from the entirety of the 2003-04 season. The Titans sank without trace.
Yet the experience of the last two courageous travellers to have alighted at Premiership Central suggests the gap might not be as unbridgeable as previously thought.
In consecutive seasons former National One champions Worcester and Bristol have not just upset the apple cart they've chopped it up for firewood and thrown rotten fruit at some of the sport's biggest names.
Both have beaten Leicester this season and both sit comfortably in mid-table with little more than a passing curiosity of the struggles besetting Bath and Leeds at the bottom.
Clearly it was in the interests of both teams to dampen expectations publicly but inside neither club started their top flight campaigns with anything other than intoxicating ambition - the Premiership is, after all, the Land of Opportunity and European travel.
Yet it's not just the league table that supports this theory, a closer look at the players reveals more and more National League products are finding success in the top flight.
Bristol have Shaun Perry, whom some would have us believe is the next England scrum-half, Dan Ward Smith and Lee Robinson, as well as three-quarters of the side that won promotion as regulars in their side this year.
Worcester came up and similarly fielded 75 per cent of the men that took them to the perfect National One season, on a regular basis. A third of the team that won all 26 games still feature prominently.
Jonny Tuamoheloa came from National Two but has not looked out of place eating at the top table. What about Terry Sigley, Chris Budgen, Lee Fortey and Kevin Tkachuk? Men from just one local club who've found no trouble breathing and prospering in such a rarefied atmosphere.
Then there's the quality of the rugby. Anecdotally, two years ago Pertemps Bees slaughtered a Wasps side made up of full-time professionals.
A bunch of teachers, electricians and bouncers blooded the noses of Mark van Gisbergen, Trevor Leota, Peter Richards and Simon Shaw - literally in the case of the last case.
And watching Worcester and Northampton labour in difficult conditions last Saturday it was easy to believe, had it not been a cup weekend, National One would have been replete with fixtures similar in style and skill.
Then on Monday night I watched a young Moseley second team (remember what one of those is?) batter a Worcester side made up of academy players and fringe first-teamers.
Although Matt Maguire and Saosi Vaili looked a cut above, the vigour and enthusiasm of Moseley players like Paul Cox, Tom Skelding and Carl Colvin gave some of their more illustrious opposite numbers, established professionals such as Gary Trueman and Jonny Hylton, serious food for thought. Moseley were well worth their 17-15 victory.
Which brings us to the next club likely to attempt to bridge the gap, Harlequins. Although they are the best side in National One and promotion seems assured, they have been given more than the odd scare in this season. Who knows what might have happened had they not scored a late winner at Otley?
Yet when they return to the Premiership they will be better equipped to deal with its demands having been given a bashing at Cross Green and encountered near suicidal defence at home to Bees. Crossing the gap, after all, merely takes a leap of faith. Worcester and Bristol have shown that.