Actually in America that is quite easy, " Emirates Nine Twenty Seven, Emirates Ninety Seven, and Emirates Ninety Nine Twenty Seven". This fixation with reading call signs as single digits is half the problem.
If I am EK 151 right behind EK 15 I sure as heck don't say "Emirates One Five One", I would instantly become "Emirates One fifty one" if he is transmitting as Emirates one five. The uptight people who insist on standardized phraseology at times like that need to loosen up a little.
So what does UAE51 become...........?
I'm not sure how anyone can argue that there is no chance of confusion between 'Emirates one fifty one' and 'Emirates fifty one'..........And I second what Helen said.
Just because there hasn't been a major incident in this airspace yet due callsign confusion, doesn't mean it's not going to happen. Surely it's a good idea to try and negate any potential future incident as much as possible.
That's what Swiss cheese models are all about.
Our industry that we all work in has an unfortunate habit of only fixing things AFTER an event. I agree that alphanumerics are definately a step in the right direction.
And anyway, isn't the registration of the aircraft you're flying on a little plaque on the dashboard? How hard is it to read the last 2 letters of that on the rare instructions you're going to be asked to do so?