R. (on the application of JH and FW Green Ltd) v South Down National Park Authority [2018] EWHC 604 (Admin)

“66. With one minor gloss, I respectfully agree with and adopt the approach of Cranston J and Foskett J in the two Gibson cases. To my mind, they emphasise the need for alternative proposals to be demonstrably substantial rather than speculative before they can realistically be considered as candidates to be the optimum viable use. A proposal which is merely speculative is not viable, whether or not it might otherwise be optimal. This is, to my mind, clear both from the current guidance and from the Gibson cases. The gloss is that I can envisage circumstances where the difference in the level of harm inflicted by two proposals was limited so that, although one would be regarded as the optimum viable use, it would not be right to regard that as a compelling basis for refusing permission to the other if the overall balance between harm and public benefits favoured the other. This serves to reinforce that the planning authority’s task is to weigh any harm to the significance of a designated heritage asset against the public benefits of the proposal and that securing optimum viable use is only one part of that balancing exercise.”

R (Gibson) v Waverley Borough Council (No. 1) [2012] EWHC 1472 (Admin) and R (Gibson) v Waverley Borough Council (No. 2) [2015] EWHC 3784 (Admin)