CULT: request for info re: winter strategies

A couple of us have been thinking about the different ways cultivars of
bearded iris 'cope' with winter in cold areas with no snow cover.  

They seem to respond three ways - 
1) keep trying to grow during every warm spell and get repeatedly
injured
with lots of diseased foliage, 2) wait for spring, with injury to ends
of leaves that gradually die, but don't seem to have all the lesions and
spots of the others, 3) cut their losses and disappear - these are
impossible to find amongst even short weeds - fans are only an inch or
two tall at most, but what is there is very healthy and green.  

For sake of discussion (and out of my own ignorance of other descriptors
maybe
previously used) let's call these non-dormant, partially dormant, and
fully winter dormant.  In my kind of climate (rare snow cover, lots of
big changes in temperature from hard freezes to balmy summertime (like
today - it's absolutely muggy out there), through several cycles every
winter) the fully dormant strategy will always be effective.  

The partially dormant strategy works pretty well, but provides more
opportunity for disease and injury unless the foliage is incredibly
resistant to injury (like HARVEST OF MEMORIES, STAIRWAY TO HEAVEN).  The
non-dormant strategy only works here if the plant is a super vigorous
grower with the capacity to replace damaged foliage faster than it loses
it (CELEBRATION SONG is especially good at this).  

I just walked through the garden and came up with a very
short list of the fully dormant ones, and they are all good performers
here - I. pallida (blooms early so buds/flowers are often damaged), I.
germanica (ditto), WINDWALKER, SULTRY MOOD, WABASH, MULBERRY ROSE,
COLETTE THURILLET (new this year, forgive spelling attempt).  I forgot
to check the clump of VANITY, but I think it does this also.

So my request is to anybody on the list who is in an area where there is
no snow cover and cold enough temperatures (below 15oF?) to knock the
leaves off.  I would like to know of more cultivars with this winter
growth habit, especially recent ones (1980s or later).

Thanks in advance.

Linda Mann east Tennessee USA
overnight lows in the 60s are typical in JULY!  And in January, I guess.
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