I would tend to agree that excluding improperly run cables and such, you shouldn't break a rudder cable, however, I have a story that may give some folks pause.

 

A few years ago, I was rerigging the standing rigging (stainless stays and shrouds) on my  then 28' sailboat boat as is prudent every few years.  I had all of the wire replaced and the new rigging done with rotary swaged stainless fittings as I've always done.  I pulled out the the mast and put the new rigging in, put it back up and tightened it and everything looked good.  Then I went sailing and tuned the rig. Still OK.  Then I did a race and in the first real load, One of the fittings pulled off of the wire!  Fortunately, we didn't loose the mast (I still don't know how that stayed up), I've had other dismastings and they aren't as much fun as they look.  That was the only one of all the new wires to ever do it so apparently the fitting was incorrectly sized.  Like maybe it was metric, but the bottom line is, you can have failures on all new fittings whether you have done your part correctly and whether or not the wires are correctly sized and run.

 

Sleep well, all you biplane owners!

 

Dan