BOAC,
Having worked at an airfield that has to use the first exit to depart traffic from,then you are instructed which taxiway to vacate on quite clearly.This is after you have slowed to taxi speed obviously.
It doesn't stop pilots from trying to turn into the blocked taxiway(crap driving,failure to prevent a collision,ignoring ATC instruction
).
As far as the incident goes then the OJTI maybe didn't have sufficient time to try and stop the aircraft turning,or didn't see the aircraft try to turn on the RET.Perhaps they simply forgot the Cessna was there,as it's small and may not have been on their frequency.I'll stick with mistake.
I'm with HD as that's the way I've had to control for a long time due to airfield layout,and I haven't had a Golden Towbar award yet.
