IMHO an emergency does not necessarily make unapproved operation outside the
envelope desirable or acceptable.

No. But it does make the benefit (of better control) more likely to be
worth the cost (of damaged parts).

What concerns me is that exceeding the gear (or flap) extended speed makes
you a test pilot. I do not think that inside a thunderstorm with severe and
random loadings is the time to experiment with unknown flight
characteristics or of the structural strength of the gear doors or of the
increased surface area exposed to possible icing.

If you are inside a thunderstorm you are already a test pilot. You are
getting close to being an ex-pilot. One would need to weigh the benefit
of the extra stability (of lowered gear) against the cost (of putting
known loadings - gear extension is not random) on an aircraft which is
being buffeted around like a banana in a blender.

Icing on the gear is much less important than icing on the wing, and if
that's what it takes to keep the wing attached, I'd make the trade. I
agree that flaps are probably not good to extend, but everything I've
read indicates that gear down is a good idea (in fact, put the gear down
before entering if you know you must enter).

Never been there, never want to, decide (either way) at your own risk.

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain."
(chapter 10 of book 3 - Harry Potter).
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