If you want to understand why American pilots have so much trouble with standard RT, watch a film called "Idiocracy" starring Luke Wilson. It illustrates the direction in which the USA in general is headed and especially their grasp of verbal communication.
Like a lot of their TV, Yank RT seems "cool" but bears little resemblance to reality.
Yank RT Translation:
Okaaaaay = I am about to start speaking,
...is with you = I am on your frequency in case this isn't obvious by me transmitting,
checkin' in = I am on your frequency in case this isn't obvious by me transmitting,
two one point three = Passing flight level 213 or maybe flight level 21.3 (2130 ft ???)- who knows??
twenny eight fourteen = Squawking 2814
with the flash = with ident. Not a required call anyway.
lookin' fer lower = Request further descent
Unnerstand one five oh = read back with no acceptance of responsibilty - I only understand the clearance to be XXXXX and it's your fault if I have it wrong.
oh = zero
Twenny three an' a quarter = one two three decimal two five
An' = and
Maintain two five oh = maintain heading 250 or maybe FL250 or maybe 250 KIAS. Who knows??
Look at Flying Tiger 66 for an example of crap RT leading to a crash.
The USA may have the best safety record as someone claimed (I doubt it) but sadly they also have the record for the dumbest causes of accidents:
Looking for spare light bulbs, teasing the FO, reversing out of an iced-in parking bay with reverse thrust (!!??), no flaps for take off while chatting the stewardess, etc, reading back 2400 as 400 feet, many more.
Use it at home, leave it at home if you're going to fly in the rest of the world!