McFarlane LJ held at para 50 in Re G that “The linear approach, in my view, is not apt where the judicial task is to undertake a global, holistic evaluation of each of the options available for the child's future upbringing before deciding which of those options best meets the duty to afford paramount consideration to the child's welfare."
A court cannot apply the yardstick of proportionality in its consideration of what is necessary without having evidence about the options to which it can apply a welfare evaluation. As McFarlane LJ said in Re G at :
What is required is a balancing exercise in which each option is evaluated to the degree of detail necessary to analyse and weigh its own internal positives and negatives and each option is then compared, side by side, against the competing option or options.
In Re B-S (Children  EWCA Civ 1146 at , the court suggested that it may be helpful to those who have to perform this task (and the associated task where placement applications are made under the Adoption and Children Act 2002 where the separate and distinct welfare checklist in s 1(4) of that Act is engaged) to adopt the balance sheet approach first used by Thorpe LJ in medical cases (see, for example: Re A (Male Sterilisation)  1FLR 546 at 560). Setting out the positives and negatives or if you prefer, the benefits and detriments of each placement option by reference to the welfare checklist factors is an illuminating and essential intellectual and forensic exercise that will highlight the evidential conclusions and their implications and how they are to be weighed in the evaluative balance that is the value judgment of the court. It is to be noted that this exercise is different in substance and form from a mechanical recitation of the welfare checklist with stereotypical commentary that is neither case specific nor helpful.