How will you circulate this magical CO2-laden fluid into the bowels of the earth and have it react when the rock has no porosity or permeability? We are talking about the mantle, not a beach sand.
The point, surely, is that there is an awful lot of CO2 bound up in limestone in the earth. That CO2 was in the atmosphere, and now it ain’t. So if you want a lower CO2 concentration in the atmosphere, you would like to replicate the process which sequestered all that formerly atmospheric CO2.That was what I got from the article, maybe I’m wrong . . .
And maybe the idea that the biosphere is better off with de minimus CO2 than with the CO2 levels which prevailed in the past - and which have not had obvious detrimental effects as of now - is what is wrong.