Perhaps I'm missing something but it looks to me like the use of this additional phraseology has served a purpose
ahhhh if only things were that simple.
Could it also be a product of the mindset of both pilots and ATCO's alike that this issue has been highlighted?
Could it be a product of the processes at work?
Is it a product of the increased awareness from CP's down to the average line pilot, along with numerous NAT's publications, safety notices, and company aircrew memoranda that has served to improve the appreciation of the nature of the level bust issue.
Pilots confusing a level and heading instruction i.e climbing or descending to the heading rather than the cleared level used to account for 11% of level busts in the UK.
All this shows is the limitation of the system currently in place, it also highlights why phraseology has its limitations..because the word "degrees" is open to misunderstanding.
Then again what would I know, I'm clearly a majority of one in this thread.