I recall a statement from TSB in canada about their threshold to conduct an investigation. Although the exact words escape me, perhaps its on their website, (its sunday and I'm in my jammies with a tea and am too lazy to search for it.)
it pretty well summed it up as an investigation will only take place if there is an outcome to further enhance safety. Referring to the incident of carb icing on a small plane, there was nothing new to learn, so the investigation was minimal.
Me thinks another down wind landing crunch fits that category