Fair dinkum! "I'm better at R/T than you are"... strewth...
I've never had a flight, anywhere in the world, where pucker ICAO phraseology was used. I thought the point of comms is clear communication over radios even with poor reception to ensure flight safety. If ATC don't understand the response or aren't happy with it they say so - same the other way around. So if both parties are happy, what's the big deal? Sure, on congested freq you should stick to the basics and keep it professional - if nothing else, it minimises the chance of misunderstanding leading to a second call.
There were slack-arses who would also reply to an ATC instruction to descend to flight level 210 by saying "Flight level 210, left 350" when there was no way the aircraft had commenced the descent in the 3 seconds it took to reply.
You'd have to ask Mrs Trash if I'm a "slack-arse", but there were plenty of times I was held up by ATC so when the clearance
finally came, I was descending in the 3 seconds they took to finish their call so I could get down to stabilise my approach prior to the final fix.
Very much depends on what is said, where and when. Airmanship will guide you...