'...we'll end up with a punch up on mat...'
'...So far it has happened during one of my gradings...'
So, what has that taught you?
'...We practise a very 'positive' style of aikido, I assume you do not?...'
Whatever 'positive' means...
And how can you possibly assume anything?
And what's wrong with takemusu aiki?
'...there is a difference, subtle albeit, between a grading and a demonstration. Think about it...'
I assure you, that I've had a much longer time than you to think about it. And the impression I got from your original post is that YOU haven't thought about it long enough, if at all.
'...Im sure i'll be visiting Oz to train at some point in the next few years!..'
I don't drink beer, but drop me a line - I look forward to a discussion and training. Things may look very different on the mat. A couple of my students are poms and my very good mates, by the way