Re: So there's no taboo
Yes, yes. I understand you're the UK and there are no taboos over there except maybe publishing an actual Charlie Hebdo cover. But that's not true everywhere.
I can assure you the distinguished Prof is talking out his ass. One of my early jobs was working for a NPO in the US which was intimately involved in the regulation of fertilizers and pesticides. The farmers want to know the least amount of fertilizer they can put down to maximize their crops. Same thing for pesticides. If they could get the same crop yields without using either they would. Because at the end of the day they're just like any other business: they want to maximize their profitability. It isn't simply a matter of passing along the cost. Money not spent on fertilizer can either be money in your pocket, or money on expanding your farm to make more total profit.