We've Got Your Number, Not!

Can we ask all runners that as/when they pass the finish line and through into the funnel of races that they make sure the officials can have a clear view of their race number. There have been a small number of instances where runners have briefly obscured their number by reaching across their bodies for their watch/GPS to stop that instrument recording. This does cause the officials problems, particularly the timekeepers at the front of the funnel who are "spotting" numbers in advance of the line.