i think when charge mentioned interconnect, he was referring to the connection in the die itself...we can only see the die but inside the die is like a big metropolitan traffic, higher here and there, cascaded some more...so the hotspot maybe at some of the curve...where the place most 'accident' occured...after some time, the wall may not be able to take it and collapse...so, in the proc world...even one interconnect (junction?) collapse or break, u'll have disconnection...circuit that have disconnection will not be working, isnt it...
so 50c probably the die temp...but we just dont know how high is the temp for each interconnect in the die...so there IS a probability that the proc will die on you...
those guy in XS does not retain their proc for long...the buy, they oc kaw-kaw and then probably sell it off to get another better proc...and life goes on!

after reading the safe voltage range in your post...i've tune down the vcore to 1.35v (or issit 1.36xx)...now priming at 3.2G...if no prob, then i will stick to it for 24/7 and btw, i will not be keeping this proc for 10 or 2-3 yrs...less than 1 yr maybe.