Are there any contra-indications to storage at minus 80?

My thoughts have always been that the lower the temerature, the 
slower the reaction - any reaction.  (Don't get sidetracked!!)
We are talking here about chemical reactions in the broadest 
sense and it is they which cause antibodies to "go off", meat to rot, 
reagents to "age" and bugs to grow.
The lower the temp., the more these reactions and these outcomes 
 are inhibited.

Problems are caused by:
1 Repeateated freezing and thawing - issues well rehearsed in 
these columns.
and
2.The rate of thawing, and the example I always give is red blood 
cells are not lysed by freezing but they are by inappropriate 
thawing (generalisation, OK?)

So, do some antibodies NOT need storage at minus eighty 
because they "go off" more slowly than others, or because they 
thaw "better" from minus 20 than from minus 80?

Is my premise that everything can be stored at minus 80, but only 
some things at minus 20 right or wrong.

Is my premise the lower the temp the better right or wrong - given 
the strong caveat about thawing.
Just curious.
Russ

p.s.Did you hear about the vicar and the actress on the hospital 
ethics committee?

Russ Allison, 
Dental School
Cardiff
Wales