prove it dude. Prove an over abundance of CO2 is bad for a plant. Let's see that evidence. hahahahaahahahaALL plants live off of CO2, photosynthesis cannot occur without it.
If you are deprived of salt for a time, you will die. So, since salt is absolutely neccessary for your existance, just go ahead and eat a quart of it. See how that works. For that is your logic.
Admit it, you hate humanity!!!!
That salt analogy is pseudo logic and had nothing to do with CO2 and photosynthesis.
Optimum CO2 for greenhouses:
Carbon Dioxide In Greenhouses
For the majority of greenhouse crops, net photosynthesis increases as CO2 levels increase from 3401,000 ppm (parts per million). Most crops show that for any given level of photosynthetically active radiation (PAR), increasing the CO2 level to 1,000 ppm will increase the photosynthesis by about 50% over ambient CO2 levels.