The question isn't whether they would be good or bad for the environment. The question is whether erosion control structures are an appropriate erosion response measure, given everything we know about the direct, secondary and cumulative long-term impacts associated with them.

From an economic perspective, spending $10 million upfront - and then another million or so every year - to extend the life of a handful of threatened structures that provide maybe a few thousand dollars in tax revenue each year just doesn't make sense.