It is indeed saying that, you can't model secondary effects and they are ignored in this analysis. If you believe trying to have the rich pay more of the gover

It is indeed saying that, you can't model secondary effects and they are ignored in this analysis. If you believe trying to have the rich pay more of the government budget is only going to lead to them paying less, no other assumptions needed, there is no discussion. I think assuming this contradiction is way too fatalistic.