wiley
This thread is about mis-use of 121.5 , the practice of using it for practice is not mis-use is is an officialy alowed practice.
I do however agree with you in an ideal world that this would be better done on another channel but then you run into the problems of duplicating equipment.
When ever I have had to use 121.5 for real in the UK all the "practice calls" have disapeared instantly.