IMHO this thread is beginning to degenerate from what is safe or not safe towards a potentially dangerous set of "what-you-can-get-away-with" opinions.
The Summary on the final page of the
Safety Sense Leaflet 3 - Winter Flying says it all.
Please read it. Do not fly with ice or frost or snow on the aircraft and do not fly in icing conditions. It is really quite simple.
JD
