Here's a question. What is the point of Hi Viz? To be seen, right? So why are the hi viz jackets not made in the most visible colour, which research (apparently) has shown not to be yellow, but flouresent pink? OK so people would be reluctant to wear them............... just like the yellow ones.
If the speed limit on aprons is 10MPH/ max taxi speed is walking pace can't walkers and cyclists get out of the way?
Finally I am convinced that most people are run over airside not because they were not seen, but because the driver was not looking where they were going. It's just easier to say on the safety report that they couldn't see the person they ran over.