Convincing 10 people to CONSISTENTLY AND FOREVER decrease their meat intake by 10% is the same as convincing just 1 person to go vegan (aka 100% reduction).

I don't think so. 10 people reducing it by 10% is nothing in a society where everyone claims they have reduced it and only eat happy to be killed animals from their uncles farm. On the other hand one vegan could show hundreds of people that there is no magic to not abusing animals and change some. It is not only about the personal impact but when veganism hits a critical mass and changes society.