We had a talk form a very familiar Insurance Company and the guy was tellling us about some recent cases.
He went on to explain that they dont refuse to pay out if there is some small technicality (you can always find one) but may start to debate when there is a long line of invalid documentation...as so often is the case in accidents involving a pilot with some sort of "form".
This may not necessarily relate to aircraft docs (if hired) but personal documentation, i.e. licence , medical, lack of IR or IMC Ratings etc...mmm... you only have to look through AAIB Bulletins to see this.
He cited the Colin MacRae case where they arrived at an "agreement"...