Two broken bass strings in one tuning?????

[Mike Kurta]

    Sam, in my view, there is no clear answer to string breakage.  When I 
first began tuning, I dutifully applied Protek to string coils and capo and 
v-bars, and found no difference in string breakage as opposed to the pianos 
I didn't treat.  The same with lowering the tension first.  I've tuned old 
uprights that sat on a porch for years and were nothing but a ball of rust, 
and 150 cents flat, overpulled by 50 cents in one shot, and fine tuned 
without breaking a single string.
    I've also seen 1 year old pianos break strings after just nudging the 
string sharp.  I've now adopted the policy when junking old pianos of 
purposely breaking all the strings by cranking them tighter.  Again, some 
break immediately, with others I can turn the pin a full half turn before 
the string breaks. This tells me that there is no rhyme or reason to string 
breakage, and predicting is nearly impossible.  Slow pull vs. jerk tuning 
doesn't seem to have a pattern either.
    Just my 2 cents.....
    Mike Kurta