Always wanted to fly the B 222, but I dont dig the ice flying!
I IFR climbed through to 6000 (which was LSALT) at 2 degrees indicated in a UH60 when the ice detector suddenly went straight to "severe". And severe it was - I looked outside on to the leading edges of the external fuel tank support wing and fuel jug to see a layer of ice building rapidly. The ice continued to build until about 2 inches had accumulated. There was lots of vibrations as expected, and torque changes required between the anti ice and de ice systems shedding, but the stabilator kept failing due to severe ice build up and had to operated manually. This experience has given me a very healthy respect for the rapidity with which ice can build up, and the severity of the consequences of accumulation.
Now that I fly machines without anti or de ice capability, I tread very carefully. My IFR climb checks include a temperature check going through each 1000 ft. At plus 4 deg I would stop my climb where at all possible, get the copilot/crewman to begin a scan for ice build up, and we use the torch at night. Below 2 degrees, there has to be a very good reason for me to continue the flight (ie medical) and I use other routes to lower my LSALT if possible, and as a last resort now that GPS is all kosher, I will calculate my LSALT based on present position rather than over the entire route so that I only have to fly at higher alts over very short distances.
oxi: I seem to have a different philosophy than you, but I am suprised that you can get over Cumulo Bastages at only 10,000! I am assuming that you have WX Radar - thats what I will use to avoid embedded CB (apart from trying not to get airborne in the first place!!).