Thank you, Nigel. I may believe that those benefits are outweighed by what we lose but at least you have made the effort and I appreciate that. Sadly, while the losses are quantified by the various studies linked in this thread the benefits do not seem to have been subjected to the same scrutiny. I find that rather disturbing and would be happier if they could be quantified by more than sticking a set finger in the air. Hence the ask.