Obviously I don't know the facts of this case, but it frightens me to see the complacency of highly trained and experienced ramp staff and engineers.
. Approaching aircraft while they're still moving, slowing down rotating propellers by hand, walking behind taxying aircraft, etc.That said, it seems to me that they're always under pressure from aircraft and airport operators to get the fastest turnaround possible. Perhaps a fact our flying colleagues would consider in the hubub of the turnaround time. Unfortunately, despite all the training that goes on on, I don't think that this sort of incident will ever be eradicated.
I think that the painted props were withdrawn due to the possible hallucinatery effect they have upon the brain.
Look at a fast rotating black and white propeller for 30 seconds, then look at the ground - there's a very good chance you'll fall over.