Whoever wrote this is going to have to write another one, the hundredth monkey effect, I don't know. As to the rest of the question, we don't believe that we are doing anything while we're doing formal meditation that's going to change other peoples' Kamma. We don't believe it's a prayer, when we meditate sitting or we stand still, doing Compassion and Lovingkindness, is for us, we're changing our heart, we are conditioning our heart to be more open to every living being on the planet.
We are not saying that we will change others while we are doing formal meditation. However, if you haven't already seen any of this in your own life, the more you change in your formal practice, that will effect other people. It's very real, a person who becomes more loving, will then be more loving when they go into the shop, go into a restaurant. Other people will sense that, and often that will encourage people to be more loving in return. They become examples, someone who is loving becomes an example.
That makes me remember my eighth grade mathematics teacher, who was stern, someone when we all walked in the first day, we all thought "yuck." You know, all of us were little kids, thirteen years old, in those days, it was (now I'm not saying I did it) a lot of kids throwing gumballs and things. But this wonderful woman emitted a caring and love that didn't take us long to sense. And it was quite inspiring. So the more you develop opening in your formal practice, hopefully you can take it into your life and emit that in some way, which will then encourage others to change, and in that way, kammicly, help them out of some of their Dukkha.