While this is quite effective, the cinder-block ball is not very helpful.
But like everything else, it's 3 sizes too big.
It's all about getting stops!
To me, this is similar to ripping off your front car door to replace a rear car door that got knocked off. No ground has really been gained!
You know those games of baseball that all the kids played in the street, and they had to yell "car" every time a car was coming? Yeah, it's kind of like that.