In recent days it seems like the running Gods have been indulging in some fantasy athletics with double Olympic champion Mo Farah set for a starring role.
Firstly a 'catchweight' race over 600 metres between Farah and the world's fastest man Usain Bolt was proposed by the impish Brit at the London Anniversary Games. The idea was warmly received by the Jamaican Olympic superstar. Then it was announced that this year's Great North Run will feature a three-way tussle between the dominant male figures in long distance running of the past 20 years, Farah and Ethiopian legends Kenenisa Bekele and Haile Gebrselassie. Both developments have had fans of the sport salivating at the prospect. But what will either race truly tell us about each runner that we don't already know?
Let's take the Farah-Bolt match up first. It's the type of race that would have been unlikely in any other era. Could anyone imagine Carl Lewis and Seb Coe ever going head-to-head in this way in the early 1980s? Bolt and Farah are friends, they share the same agent and both seem happy to share the spotlight. Both are financially comfortable and with any race proceeds being earmarked for charity, any race would be a fun occasion.
What the race should not do - and will not do - is decide who is the better runner. No matter what happens, it will not answer that question because the result will be irrelevant. In a sporting context, the race will be as meaningful as Roger Federer taking on Tiger Woods at snooker.
Although Bolt and Farah are both runners in the same sport on the same track, what they both do is actually quite different; more so than casual observers of the sport might realise. Bolt is the undisputed king of 100m and 200m sprinting. He does so by through his honed physique which is built to generate enormous power to enable super-quick forward propulsion for a limited time. His recorded times over 400m also indicate he would be world-class at that distance. It may seem a very small step to 600m. But when you go beyond 400 metres, the human body is into the aerobic territory of the endurance runner and leaving behind the anaerobic power of the sprinter. Indeed it's arguable that this transition from sprinting to endurance comes at 300 metres and the world's greatest 400m runners are those who have the greatest tolerance for the lactic acid that floods their muscles in the last 100 metres of their race.
In contrast, Farah is physiologically gifted and physically trained to use oxygen efficiently to enable his body to perform at a sustained level over a long period. But in terms of raw power, he possesses a mere fraction of Bolt's strength and would actually look quite pedestrian over a short sprint. What could happen is that Farah could look pretty sluggish at the start of the race and Bolt quite sluggish at the end. Over the distance of 600 metres, it's also a virtually certainty that Kenya's Olympic gold medallist and 800m runner David Rudisha would destroy both athletes. Who then is the world's greatest runner? Anyway, enough party-pooping. Farah v Bolt is still intriguing and I would certainly be interested in watching it, but in the same way you might watch TV's Superstars.
As for the Great North Run, that will have more sporting relevance. Farah is currently the greatest distance runner on the planet and Bekele and Gebrselassie are his predecessors. Between the three of them they have won all five Olympic 10,000m gold medals going back to 1996. They have also dominated the podium in long distance events at the World Athletics Championships winning a combined 17 medals, including 12 gold. Bekele is still a formidable opponent, but not the irresistible force of four or five years ago. At 40 years old Gebrselassie is still in impressive shape, but is clearly past his best. He failed in his attempts to qualify for the Ethiopian team in the marathon for last year's London Olympics.
So whilst it will be some spectacle to see all three toe the same start-line in the North East this September, it will not tell us who is the greatest of them all. Only Farah is at his peak. Indeed, if Farah wins - as he probably will - he will still have some way to go before matching the global dominance and record-breaking feats the Ethiopian duo enjoyed.
Questions will go unanswered in both these fascinating races involving all four of these giants of running. But it still promises to be a lot of fun watching.