I might add in respect of Snell's 800/880 records on grass at Lancaster Park in '62 that the pacemaker in the race, Barry Robinson, recalled that there had been heavy rain on the track the previous day and on the morning of the race. He felt that had the race been on a European all-weather track Snell's times would have been considerably faster. After the race he said as much to Snell, who years later conceded, "I think you were correct".
With modern tracks and "super-shoes" it is intriguing to imagine what Snell might have run.