Breaking strings (new angle?)

[Clyde Hollinger]

Friends:

Since most strings break at the tuning pin, could one reason be that it
has been flexed there too much during tuning?  If so, we will find
strings breaking faster in a piano where an inexperienced tuner went
back and forth, back and forth, trying to figure out where to leave the
tension.  

Would it also follow, then, that a piano tuned 2-4 times a year will
develop a breaking string problem faster than one that is tuned
infrequently?  (Please!  I am NOT advocating out of tune pianos; my
question is theoretical.)

I am almost afraid to ask these questions, but they have crossed my mind
repeatedly, and I would be interested in any response.

Clyde Hollinger, RPT