On the subject of competing environmental goals and how we might choose between them.
She gives us a good example of what happens when someone with a PhD in Elizabethan poetry gets entangled in science, even a social science like economics.
She tells us that cost benefit analyses are not the way to take environmental decisions. For they reduce competing goals, the costs and benefits, to icky money dahlings.
She then uses the Severn Barrage as an example of a better way of decision making.
Entirely missing the point that the cost benefit analysis of the Severn Barrage showed that it was a bad idea that we should not build.