I see the predicament now, we have two error messages split between plot_eco.html and plot_detail.html.

The original problem in #889 stems from the fact that the "sorry" div is too presumptuous. It does not know why ``benefits`` were not included in the context, but it gives a (wrong) explanation anyway. It may be easier to maintain this whole thing if all the decisions are made by plot_eco.html, which is passed more detailed context