Re: It is courageous to assume it will work
CO2 levels have been much higher than 750ppmv in the past. Hence all the hydrocarbons we're still digging up from those good'ol days. And oddly, also around the time that squishy things* developed backbones** and exoskeletons. An especially impressive feat given high CO2 means*** acidification. Or maybe all the CaCl neutralised all the acid. Or it's just as well they pulled that off, or we wouldn't have all that chalk that'll prevent ocean acidification.
But such is politics. CO2 levels can easily exceed 750ppmv in badly ventilated places. Pets and plants don't die. But if, say CO2 dropped below 175ppmv... Then pretty much everything dies
*Not greens. Well, some photosynthesis.
**Absent in many greens
***Or it doesn't. Greens even demo this. Drop chalk in vinegar, watch evil CO2 form. Gloss over the bit where reaction stops once the acid is neutralised. Acidification claim is vaguely true, although it's really a teeny bit less alkaline.