Baffler15,
Lazy? Yes!
No offence intended here, but as an ATC, if there is one thing that really pisses me off it is pilots who readback 'NINE' instead of 'NINER' when assigned descent.
It's amazing how much it can sound like a 'FIVE'.
Then I have to waste everyones time and seek confirmation before I can get on with the next thing.
Most of the culprits do tend to be RPT jets.
I can live with most of the other non-AIP phraseology (I'm certainly not perfect), but not this one,
Cheers.