The cracks shown in that link are exactly like the ones I found in my
20 yr old rigging. The cracks in mine were very difficult to find
until I used fine sandpaper. They were all on the lower swaged end.
Most of the cracks were under small brown stains that were the result
of the stainless in the crack becoming non-stainless and rusting. They
required a 10X magnifier to find. At work, I ground the fittings away
to see how deep they went and they went through the entire fitting. I
even used dye penetrant with no luck. I replaced all the rigging and
lifelines last year.
NOW, although thefittings and wire and rod are stainless, stainless can
be slightly ferromagnetic and can be tested via flux leakage methods (I
used to do magnetic NDT research). Furthermore, the area around a
fatigue crack is less stainless and more ferromagnetic than the bulk
material. This may allow testing via mag particle inspection
(so-called magnafluxing). It is entirely that nobody has done this
because they simply assumed that teh stainless material wouldnt allow
this to work. Unfortunately, I threw the old rigging away so I cannot
try this.