<<Frankly, it's a bit pathetic.>>
Funny, that's the conclusion I'd drawn about your post... I immediately assumed that you were a PPL but your profile says ATPL, which astounds me.
It is definitely not a new phrase. I started working in UK Controlled Airspace in January 1972 and from the first day I worked on radar I used the phrase "remain clear of controlled airspace" Why? Because pilots wishing to enter CAS would state what they wanted to do and in the absence of a clearance they would sometimes just do it. If a pilot is incapable of obeying that simple instruction he shouldn't be in an aeroplane, let alone up in the air.
"Remain clear of CAS" is en excellent phrase and does what it says on the tin..