When I first trained in Approach procedural, aircraft always arrived overhead the beacon at exactly the time they said they would. (Wonderful things ATC simulators).
Then of course, I entered the real world where the difference between the estimate and the actual arrival time can easily be 12-15mins on a relatively short hop.
Now I don't mean to point fingers of accusation at anyone here; these are purely my observations. The estimates which I receive as a procedural ATCO are in reality not pilot estimates but ATC software predictions. They are unreliable at best and at worst down-right dangerous. For this reason, it is vital to obtain an updated estimate from the pilot once the a/c is on frequency. There is always the question of honesty of course, particularly when you are in a non-radar environment. T'was ever thus.
...............................but radar is coming to the frozen North.
