Aussie Bob:
I don’t know about any of the above. IMHO what makes using a single multicom frequency unviable is simply the verbal diarrhoea that flows from most pilots mouths whenever they get the chance. In particular I single out RAA and private pilots. The clear winner here is the running circuit commentary that so many love. Goodbye MULTICOM, hello chatter.
Speaking as a PPL, you can go and get (censored). There are three issues here, all of which have killed students and inexperienced pilots.
1) The skygods like Aussie Bob who are so used to voice procedure that it is a point of honour to make a transmission so fast as to be unintelligible except to other cognoscenti. I first encountered this in military fire control, but that was amongst a small group who new each other; as in "firemission grid yabba yabba etc." The aviation equivalent is "trffc mildu ayabber yabber in 10". Unintelligible plonkers.
2) The poor feckng chinese or indian student who, despite having passed Cambridge level 3 English, doesn't have a hope in hell of deciphering what Aussie Bob said and carries on regardless in silence.
3) The poor fecking PPL like me who tries to follow CASA dictums that it is better to try and communicate than not.
....and all we get is condescending BS about making too much noise? Tell that to Holly Smith and the poor indian kid who died at YMMB.