If memory serves me well Tony, the eventual cause of failure was a poor standard fillet weld. When I delivered NC unit on weld inspection, I used the Alexander Kielland tragedy as a good example for the need for QAQC procedures. Poor quality fillet weld was missed during inspection of x-rays of the bombed area. Time and North sea storms did the rest.
I totally understand the no "reker" consumption. I had a similar policy of never go hunter gatherer near sewage outfalls while diving!!