While Cunningham is the one who has been sacrificed. I feel the blame for this has to fall at the hands of the clubs senior management.
Saints have been excellent in their player academy set up, however they have been woefully inadequate in making long term provision to develop future coaches in house.
KC was thrown in at the deep end. I recollect saying when he was appointed that we needed to be patient and not expect miracles. I suspect the experience has been somewhat humbling for KC as he took the job feeling very confident in his own ability. However that has proven not to be the case. At times recently i got the impression he had realised that he was in way over his head, but was trying to battle through it.
I hope KC can take a step back like Powell did , take on a lower championship role and then work his way through the system. In 5 to 10 years time he might become a top line coach.
From Saints point of view i hope they learn that you cant just stick a playing legend behind a desk and expect them to produce coaching miracles. Coaches are made not born.