IO540 and Humour
What a bitter and twisted rant and, even if it was supposed to be funny which it was not it demonstrates a great deal of ignorance. And FWIW I had to revert to DR on two separate occasions whilst flying the Trident, once under rather hostile conditions (but we wont go into that here!) and the other whilst enjoying difficult technical problems. We were not travelling at 120 kts either, so the outcome had to be fairly accurate in fact when in the hostile case it had to be absolutely spot on and it was (UK ATPL).