Why?
I honestly can,t think of a good reason.
I know of several Expert (names you would know)flyers that lost planes to broken solids.
Lememteen folks will jump up and say." I used them and never had a problem".
O.K. fine,me too!; But no longer.
I have been told that the quality of music wire has gotten lousey.
I know that it makes your plane about two inches wider when placing in the car.
You bend one, you got to straighten it or your controls suffer.
Bend the turns too tight and get a stress riser.
If its to save weight ; there are many other things you can do to save weight that are a lesser gamble
to the future of your plane.
Just the picture as I see it and really trying to be helpful.