absolutely right to echo that caution; i still remember in 1971 reading in the back of london's sunday times of a budding champ from watford; this is the flavour of an earlier report
JULY 18, 1969: Fourteen-year-old St Michael's schoolgirl Mary Sonner ruthlessly crushed the opposition and established herself as the United Kingdom's fastest intermediate over 800 metres at Motspur Park, London, at the All England School Championships.
Mary's incredible time of 2:12.4 seconds beat her previous best by two and a half seconds and has made many senior "half-milers" sit up and take notice.
As one doyen of the local athletics scene put it when hearing of Mary's time: "Incredible. It's almost frightening. I wonder where it's all going to end."
a year later she improved to 2:07.57 and i believe 2:04 at age 16, before quitting altogether