After countless takings on and off for comparison with other strings, my Dominant D broke. The break occurred between the nut and the peg. I took a look at the string under a magnifying glass, and I'll be darned if it appears that the core ends where the silk starts, but it's hard to tell. There are some strands of something perlon looking at the break, but mainly it looks like inner metal wrap only. Anyway, it seems to me that the problem is due to the unique construction rather than QC. I imagine that the high level of stretch that happens above the nut just causes the string to fatigue at that point after many de-tuninging and re-tunings. I guess the same thing could happen to someone who pulls the heck out of the string with some strong right hand pizz. Because of the stiffness of the vibrating length of string, you can actually see the string moving across the nut when you pizz, probably stretching the silk portion of the string more than the metal wrapped portion.
-Jon