We have at least 20 aircraft towed a day at Adelaide, from A330's and B747's to PC12's, they are towed by a vehicle with generally two persons, a driver looking forward and the engineer looking back at the aircraft. No wing walkers or spotters, at a busy airport this would be very dangerous and much less safe. The aircraft guide lines in/out and airport movement limitations guidelines provide more than adequate clearance for manoeuvring aircraft either under power or being towed, that is if everyone is aware of where they are, where they are going and do as they are instructed, then all is good. But we are human and accidents do happen, just the same as the Jetstar A320 and Virgin aircraft at Melbourne.