but is not the hard and fast 'snowing therefore no icing' rule that you advocate
And if you read what I've actually written, rather than what you'd like me to have written, you'll see that I've not suggested anything of the sort.
I entered this debate because I objected to an assertion in a cited article that "wet mushy snow" necessarily contains supercooled water. Most of the time RASN does not: it's simply snow that has melted. We seem to be agreed that encountering liquid water precip, whether pure RA or RASN, with an airframe temperature below freezing, has a significant potential for icing.
Reading what you've actually written, I'm probably guilty of similarly misinterpreting you too in what I made of the following:
I think the point was made to emphasise that ice must melt first before it can re-freeze onto an airframe so yes, a snowflake must melt before it becomes an icing risk but that is what RASN is all about.
That RASN is "all about melting" is fair enough. That it's "all about re-freezing" (because it contains supercooled water) is not. I think you simply meant the former, didn't you? In the words that I previously quoted from you, you wrote "can ... adhere to the airframe" not "will". That's perfectly fair.
Finally...
The weakness in your argument is the use of the word probable here
The weakness in my argument is really in my use of "absence". Can we agree that glaciated cloud has a significantly lower supercooled water content than before glaciation?