“… it is not easy to see why the actual decisions in Eustice in relation to section 423 of the Insolvency Act 1986 and in C v C (Privilege)[2006] EWHC 336 (Fam), [2008] 1 FLR 115, in relation to section 37 of the Matrimonial Causes Act 1973, should be questioned, whatever criticisms there may be of some of the reasoning.…”