I wonder, if you had enough altitude after breaking out below, would it be
advisable to perform a gentle power-off stall to find out what your new stall
speed is with the ice? Or would the new stall characteristics be so
unpredictable as to make the aircraft unstable?

The new stall charactaristics may be asymmetric, and recovering from
such a stall iced up may be a problem. If there's precip, even after
you break out you may continue to ice up, so the new stalling
charactaristics will be transitory, replaced by even worse ones.

I'd stay the hell away from stalling while iced up.

Jos
--
He who laughs, lasts.
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