There is some argument about whether pension accumulated prior to the marriage should be included or excluded (that’s one for the lawyers).
If the outcome will definitely be a pension sharing or attachment order, then there is a good argument for not spending good money calculating whether the CETV is reasonable. However, this assumes that the way that the shares are implemented is not detrimental to either or both parties. Often they are not, and this is an important area where actuaries can and should add value.