> it makes concrete wobbly-wiggly. That is why i wrote "some flexible substance[ideally only at higher loads]," yes, it can make positive impact on many use-c

> it makes concrete wobbly-wiggly. That is why i wrote "some flexible substance[ideally only at higher loads]," yes, it can make positive impact on many use-cases. But I think we should focus more on the production of cement with negative or neutral CO2 yield. Cement is one of the least blamed cause of CO2 emission, but It really should be blamed.